So, I probably shouldn't like this as much as I do, but I like it anyway. Here are my suggestions.
1. I'm not sure what to make of all the weapon sounds; at present it seems like every spawned NPC just has a weapon by efault. I think it would be better if you used the dropper to actually drop said weapons in areas for them to pick up.
2. Add a d key to the dropper. Essentially, unlike the s key what this might allow you to do would be to drop a random item at your location, meaning that if you're at 23 11 your item would just be dropped there rather than having to go through a selection menu where you have to type x, y, number of items to spawn. Additionally, an i key which would show you the anount of items and where they're located could also be useful, as would a p key, which would allow you to pick items up if, for whatever odd reason you don't want a spawned NPC to get it just in the nick of time or something.
3. Focus. If at all possible it would be nice to set your focus to an npc. I'm not suggesting you should be able to control them, more like, look at life through their eyes, as it were. This would be incredibly useful when something like 90 idiots have already managed to wipe each other more or less out and there's still 6 of them roaming around on the board. You no longer hear all the bang bang bang but you know there's still 6 because you hit the f1 key. Depending on the size of your board they can be hard to find.
I don't know how easy it would be to add all of this in so please take it all as simpy suggestion material. Also? I'd say that, given this is your first public release of anything, you've scored a fair success. No, it's not a great game, it's just an idiotic sandbox, but that's the appeal.
I do not know what my future holds, but I do know who holds my future.