Well, I've been playing 3.1 for a few days and I've had a number of thoughts on features and suggestions. I'm sure many of them you already have planned, some of them you know you won't do anyway and very few will actually be new, but hey, the more feedback the better, right?
So in no particular order, here we go:
Ammo
Ammunition stacks need to be larger. I do understand you probably don't want people to be able to run around carrying hundreds upon hundreds of rounds for their weapons, but some of the numbers feel rather off; two light pistol magazines, for example, occupying the same space/weight as a full bag of groceries, or a shotgun? And for the crossbow and army pistol, the ammo stack size is the same as the weapon's magazine capacity, which makes it just as viable to carry around a bunch of fully loaded weapons as it does to carry a single one with spare ammunition (in fact, more so in the current system, because switching weapons is a free action but reloading is not), a rather counter-intuitive situation! I would suggest that the maximum stack sizes should be a bit improved, and should always at least be larger than the magazine capacity of the weapons they are associated with.
With that in mind I do feel that the ability to unload weapons would be a worthwhile feature. Intuitively speaking you wouldn't want to carry around a pile of heavy guns when you could have a single gun with spare ammo as a more efficient use of space/weight, and nicking the last few rounds from some poor dead sap's magazine to fill your own fits right in with the scavenger feel of the game.
NPC AI (Items)
I am aware you don't want to go into great complexity when it comes to the AI of actors, in order to keep the game running smoothly, but as it stands they are astoundingly bad at item prioritisation and inventory management. As far as I can tell, the AI will *never* drop an item, which I assume is why they always leave an inventory slot free if left to their own devices, in order to pick up food when hungry; I haven't tested to see if a hungry NPC with a full inventory will ditch something in order to pick up food, but I have the impression that they won't. What I'd suggest would be a simple prioritisation system, where each item has a default priority, and the priority as perceived by an NPC dependent on their circumstances and inventory. So, for example, an injured NPC will place a higher priority on medkits and bandages, an NPC that is in possession of a specific weapon will place a higher priority on ammunition for that weapon, and so on. Then, when the NPC is wandering around as it does, if it sees an item with a higher priority than one it already has in its inventory, it will go to it, drop the lower priority item, and pick up the higher one. Ammo for a weapon the NPC does not possess should probably have the lowest priority; food would obviously have a high priority, with medical supplies and weapons a close second; duplicates of items the NPC already has should be considered at a lower priority. Say, a bag of groceries could have a default priority of 7 (9 if NPC is hungry); if the NPC already has a bag of groceries, all other bags of groceries could be at priority 6, including iteratively through the NPC's inventory (so the second bag it has is 6, and the third 5, and the fourth 4, and so on). Clever assignment of default values (and a good set of conditional adjustments) will produce NPCs that, when possible, will sensibly choose which items to pick up and which to discard, never obsessively prioritising one type of item (like food) above everything else thanks to diminishing priority for duplicates, trying to keep a balanced inventory including food, medical supplies, weapons, and appropriate ammo.
This is computationally quite simple as well; you can easily store what the NPC's priority is for each slot in its inventory and the values only need to be recalculated when the inventory changes or the NPC's status does (becoming injured, hungry, or tired). The system could also be used to more sensibly inform an NPC's choices on what they would like to trade for what.
Pushing Things
Please make it so that we can push objects through open doorways. I guess ultimately this one doesn't make a great deal of difference, but it gets kind of frustrating when you have to smash open every doorway between you and your intended destination to get a bed to your base, and can be quite annoying if you've found a particularly sturdy door you'd like to barricade yourself behind, but you'd be forced to destroy it entirely to get a bed in there.
Barricading and Construction
The ability to barricade is very nice, but rather limited at the moment. I feel an improvement would be making different smashable items produce different amounts of wood; so smashing a chair or bedside table thingy would only produce a single plank, but dismantling the bigger, sturdier armoire should grant a full 3 planks of material. Things that are easier to break should grant less material, generally; bigger, sturdier objects, especially ones that fully block travel instead of just limiting to hopping, should give you more material.
FOV and Weapon Range
A quick investigation seems to suggest that the range for weapons and FOV distance is calculated differently. FOV seems to, as would be expected, account for diagonal distances properly to produce an approximately circular field of view (although FOV 2 produces a bizarre visibility pattern), but weapon range does not account for greater diagonal distances - as I just checked, an enemy offset to me by (4,4) was still displaying as within the hunting rifle's optimal range of 4. I noted an earlier discrepancy when one particular opponent shot me from outside my FOV, in bright daylight - FOV 8 - with a weapon that has a maximum range of 8. This was very confusing, and although I can't claim that the AI was cheating - for all I know those opponents are blessed with greater visual acuity and a better FOV than the player character, so they could feasibly have seen me over that distance - weapon ranges and FOV distances should both be calculated the same way, and it's possible you're not correctly checking that an enemy can actually see the target they are shooting at (in the example I suffered the foe had already been alerted to my presence and I was attempting to run away, a couple of steps after which I was shot, so perhaps you're only checking if the NPC's target of attention is within their weapon range and not within their FOV in determining whether or not they try and shoot at you).
On the topic of FOV, I'd like to suggest a new Skill - Perception - which could either offer an increase in the character's FOV at a 1/level ratio or, less powerfully, simply negate penalties applied by darkness or weather conditions at the same rate. Investment would obviously be a benefit to players that have to venture outside at night, and help everyone get the best mileage out of their longer-range weapons even when visibility would normally be too poor.
Follower Control
Much more precise control over the behaviour of followers would be desirable. Attempting to manage their inventories to give them sensible equipment and items is a nightmare at the moment; the ability to direct them to give to you or drop a specific item would be fantastic. It could probably do with only being available to use on followers you have had for a certain minimum length of time, however (say a day) in order to prevent people abusing it by getting a follower, demanding all their useful stuff, and then letting them loose again. The ability to order followers to equip or unequip specific items would also be very useful.
What would also be nice is more precise control over how the AI responds when on Guard or Patrol orders; raising the alarm is all well and good, but I'm sure many of us would prefer that the AI we instructed to guard a doorway actually stay and shoot the zombie using the amazing weapons we painstakingly attempted to get them to take and then continue to stand guard rather than running off to find us. A single directive option to either Abandon Orders or Keep Orders on an alert would probably handle this fine.
Cover and Positioning
It can hardly escape note that some of the enemies you will face have guns, and so rather than a stand up firefight-or-flight, it'd be nice to be able to try and take cover behind all those abandoned cars lying around. This one would be, I think, quite simple to do; you're already computing a path for the shot, simply check to see if the last tile it goes through before reaching the target tile contains a car (or potentially any object that could provide cover), and if it does, reduce the chance of it hitting (or give it a chance to hit and damage the object instead, if potentially destructible objects can be used as cover). This extends the use of all those cars beyond stamina-draining zombie-blocker and makes them objects of tactical consideration even when fighting enemies that use weapons.
On a similar note, thinking about jumpable objects, it would be nice if being on a jumpable object provided bonuses in melee - it's easier to attack down than up, so when you have higher ground relative to an enemy, you should be harder to hit and more accurate/powerful with your downward swings! Again this makes combat more interesting against melee opponents, as instead of always taking advantage of your superior speed to kite enemies, it would be a viable option to leap atop a car or table and stand your ground. It could be an especially useful technique against those zombie foes who aren't zombie-slow, and hence for whom kiting is not nearly as viable an option.
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All those things said, playing the game has been quite a lot of fun so far, and I look forward to seeing what later versions look like.
