I hopped on the Humble Bundle and have been playing the game quite a bit the past few days. It's been quite a bit of fun, despite the initially sharp learning curve! As I played, I kept a text file with various ideas I had for improvements. There's enough of them that I felt compelled to create a forum account and drop them in here.
Bear in mind that I haven't yet experienced all the game has to offer. I've reached the glow, but not yet made it inside DMC yet. That said, here's what I've come up with so far while playing. There's a lot, and I tend to be verbose. Sorry for the long read, and if this is a repeat of other peoples suggestions, then sorry for not using the Search feature. :)
- UI: Inventory Tiles
When a tile is occupied on the inventory grid, it should have a lighter grey background to more easily indicate which tiles are free. Also consider, if possible, if an item is new (just added to ground grid), have a light blue background to differentiate it from items that were abandoned earlier or from an earlier scavenging attempt.
- Condition: Uncomfortable Feet
I saw you had a post suggesting you wanted blisters, so this may already be in the to-do list, but I was also finding it illogical that one could wear footwear on the wrong feet without penalty. This condition could inflict a penalty somewhere between Barefoot and properly equipped boots.
- Condition: Gangrene
If a crippled limb is not treated properly, advanced infection could lead to this state. Can be managed with antibiotics, but is fatal if not treated (blood poisoning, reduced immune system). Requires a visit to the Clinic to amputate the gangrenous body part. This limb becomes functionally disabled until a prosthesis is procured.
In the case of a single leg, a cheap prosthesis is given, but it hobbles the player with a heavy movement and evasion penalty. Cybernetic prosthetic legs restore normal movement. If both legs require amputation (and the player somehow survives long enough to get to the Clinic!) and the player does not have enough money after the operation for at least one Cybernetic replacement, consider one of two options. One: The player is wheelchair-bound. (This may have too many design challenges to implement, perhaps results in an immediate game over.) Two: The hospital offers to install a prosthetic leg, but the player incurs a debt. They may make payments; if this debt (plus interest) is not paid regularly, they will send out a limb collector to kill the player and take back the limb (if in the field) or arrange for an "accident" (if the player enters DMC, Zom Zom's, or any other such logical landmark where there is some semblance of civilization).
Consider a similar scenario if both arms/hands/feet end up similarly amputated (give the player one arm/hand/foot to work with until they can pay off the debt.) Consider as exceptionally rare loot drops from slain NPCs (can be sold on black market for greatly reduced value? cannot otherwise use, it was designed for someone else's body structure!)
While acclimatizing to their new prosthesis, the player incurs a "Physical Therapy" penalty (...or something better named) applied to actions that use that part.
- Condition: Frostbite
If an exposed body part (hands and feet specifically) are exposed in cold weather for too long, it becomes "Frostnipped" (warning condition) then "Frostbitten." If left untreated for too long, it advances to Gangrene (see above). Can be managed by wrapping rags around the affected body part. Frostbite, when cured, regresses to "Blistered Skin." All of the above conditions impose appropriate penalties to movement, agility, and dexterity actions.
- Feature: Pack/Unpack Item
For certain items where it would be logical to do so, consider a right-click context option to Pack/Unpack items. While packed, they take up fewer tiles in inventory but cannot be used. When unpacked, they can be properly used. They contain the same mass in both states, so the effect on encumbrance does not change. The only thing I can think of offhand where this would apply is in the one sleeping bag. In a sense, clothing already does this. Not a useful feature until there are enough items that warrant its addition.
Also, it would require a complete change to inventory management, but EVE Online's system that tracks volume (to see if it fits in a container) as well as mass (to see how it modifies velocity--or in this case, adds to encumbrance) isn't a bad way to go. That may not fit within the scope of your plans, but I wanted to mention it here.
- Item/Feature: Glass Jars, Canning action
Glass jars (Mason jars, pickle jars, etc) could be scavenged in civilized areas (populated or otherwise) and used in Canning recipes to produce foodstuffs that degrade exceptionally slowly.
Crafting Recipe: Metal Sauce Pan + Heat Source + Water + Jar + Food Item
Crafting Result: Metal Sauce Pan + Heat Source + Sealed Jar (with food item inside)
Using "Empty Out" turns the jar from Sealed Jar to Glass Jar (effectively breaking the seal), and the food item into a non-preserved version of itself that degrades normally. For example, Preserved Berries would become Softened Berries, Canned Stew would become Stew, etc.
Technically, you could implement this in the tin can item instead of making a new glass jar item, but cans strike me as single-use only. Once you get the soup out, you can't exactly re-seal it, even if the graphics indicate otherwise.
Glass jars should be able to endure repeated canning processes without incident, but are otherwise quite fragile.
- Items: Preserved Food
To expand on the above, some examples of preserved food recipes.
Water + Berries = Preserved Berries (or, if you wanted to add Pectin to the game, Berry Jelly)
Water + Small Meat = Canned Meat (turns into Boiled Meat when emptied out)
Water + Small Meat + Mushroom = Canned Stew (turns into Stew when emptied out)
Vinegar + Mushrooms = Pickled Mushrooms (would require Vinegar be added in; not sure if craftable...)
Berries and mushrooms retain their poisoned qualities, if applicable. Meat would retain its Human tag, if applicable.
- Item: Lentils
Found with Botany or scavenged in urban areas (uncommonly in both cases). Cannot be eaten as is, but can be combined with water, fireproof/waterproof container, and heat source to make Lentil Soup (and if canning is implemented, can be preserved for an exceptionally long-lasting, portable, nutritious meal: Canned Lentil Soup)
- Feature/Items: Fishing, fish nets, fish hooks, fishing rods, basket traps
Allows one to scavenge water features for raw fish. Fishing with one's bare hands has minimal success rates (improved by fish tickling with Trapping skill? but still pretty low). Basket traps may only be crafted and used with Trapping skill, and only on River resources, but produces larger quantities of fish/greater success rates than with nets or rods.
- Item: Bola
Recipe: Medium Strings + Stones =OR= Medium Strings + Pebbles + Flexible Cloth.
When thrown in NPC encounters, trips up the target. Ranged skill improves accuracy and condition duration. Reduced accuracy depending on cover conditions (trees in the way, etc).
- Item: Horseshoe Pack
Recipe: Medium Strings + Large Flexible Cloth (Tarp, hide, blanket)
A long pack that is easy to craft and can be slung over the shoulders (as a rifle or bow can). Possibly would need sized/coded so it couldn't hold long and/or rigid items (rifles, arrows, bows, large branches, etc).
- Item: Barbed Wire
Found by scavenging. Can be used with branches to make a Hacksaw. (Currently, no idea what good a hacksaw is, but I'm sure there's something... this was one of my later ideas, not fully formed.)
- Item: Sewing Needles
Found by scavenging. Allows one to craft improved versions of improvised clothing with Trapping skill, suture heavy wounds with Medical skill, or restore a limited amount of clothing durability (turn it into patchwork clothing if repaired too often?). In the case of suturing, a crafting recipe to sterilize Needle and Small Thread items would be needed (boil it, or use alcohol), otherwise you risk trapping infection into the wound. Suturing wounds can lower rate of blood loss to manageable levels in conjunction with bandages.
- Items: More Drugs!
Loperamide: Antidiarrheal. Reduces the rate of dehydration when sick with Gastroenteritis, Cholera, or Poisoning, but slows the recovery rate from these ailments. Reduces the impact diarrhea has on tracking. Scavenged in urban areas. (This is a tradeoff drug, used when clean, safe water is in short supply and you risk dying of dehydration before succumbing to the ailment.)
Wild Ginger: Antiemetic. Reduces the rate of dehydration when sick with Gastroenteritis, Cholera, or Poisoning, but slows the recovery rate from these ailments. Reduces the impact vomiting has on tracking. Scavenged in forest areas with Botany. (This is a tradeoff drug, used when clean, safe water is in short supply and you risk dying of dehydration before succumbing to the ailment.)
Brawndo: It's got electrolytes. It's what plants crave! Greater impact on hydration than water, but the bottle takes up more tiles in the inventory window (3x2 instead of 4x1). Useful when suffering sickness. Scavenged in areas you would normally find food, or purchased in C.Store. (And yes, I expect the final name would be something else. :) Also, for some reason, I filed this under More Drugs...)
Syrup of Ipecac: Induces vomiting and diarrhea. Increases the rate of recovery from Gastroenteritis, Cholera, or Poisoning, but greatly increases rate of dehydration and malnourishment. Increases impact these states have on tracking. Risk of aspirating stomach contents and causing Aspiration Pneumonia or (rarely) death. Scavenged in urban areas. (To be used in desperation when antibiotics are unavailable, the player has access to lots of safe, clean water or other hydrating fluids, and there is risk of succumbing to the ailment before the body can purge the toxins naturally.)
Euphorbia Ipecacuanhae: Same effect as Ipecac. Scavenged in the forest with Botany.
(Note, the above "drugs" may be redundant due to the frequency of antibiotics; it may also just be an unnecessary level of complication to the game. Also, I'm aware Ipecac is no longer used as a professional medical treatment. Regardless, there they are.)
I believe that's everything. Hope some of it is of value. :)