Ok since AI is hard to program, why not make simple AI for humans or Aliens, they dont need to do anything special like wall crawl, or anything. My idea for a mod isnt AI actually, but rather "Zombie" type mod...
Basically here is how it works...
Aliens - Dont need any wallcrawl, or base building, but rather just a simple move (jump / pounce MAYBE), attack, and evolve (Maybe, but not needed evolve). So How it works is, aliens have a base, that is tightly packed (pre-made, and it selects a random good base), where humans say have 125 build points, aliens have 200. So the point is, humans build a base and survive for the time, or they kill the enemy base, which is basically killing the overmind, which is very well protected. Aliens could also have abilities like to cloak, so AI wouldnt be ANYTHING out of Q3 range, in other words, AI can be the same as Q3 bots. And you can buy items depending on cash, NOT stages... or stages, if you'd like. Basically, it goes by stages. Stage 1, you get a constantly about 15 dretches (bots that try and kill your base). Stage 2, you get about 10 dretches, and 5 marauders, stage 3 you get about 5 dretches, 5 marauders, stage 4 you get like 2 goons, and 5 marauders, and 2 basalisks. And so on...
Now for Humans (Easiest to program)
The base is pre-made, with humans be able to jump (no buying weapons nothing, they get weapons as they spawn, as in, you spawn as nothing but a rifle, and you die and then you are stage 2, and spawn with a shotty, and you die, you spawn with shotty until next stage, where you upgrade automatically, where the system gives it to you, so bots dont need to use the armory) and basically the concept is the same. Aliens get credits, they kill bases, and humans dont rebuild, the system auto-places things for them like previously... oh and speaking of which, bases auto-heal, like aliens do. Human AI is very easy to program, because for them you just need to do search and destroy and use medic and jump... Thats it... And tell them to stand on the medi when they are low health, thats not hard... or make them regenerate health because they are "zombie like". I think this is a good mod to start with, and shouldnt be too hard... After all, you can just copy the Quake 3 BOT AI, and use it for humans, and make it where the system decides a lot, instead of you programing the bot AI to go and buy it (much more difficult to do)...
So you get the point, and you understand how this works... I hope, i know this would be a lot of work, but i got the idea from Killing Floor from UT2004, and i think this would make a lot of sense... even adding weapons that are close range such as a sword (replace blaster, make it not show an animation, and make its range smaller, and model something different by porting some type of mod) thats just an idea... but all you need is just some AI thats basic, and some system changes so it all works out in the end. This is just a beginning for trem and bots, and i believe human AI isnt that hard, you need spawning like it is now, and an ai... nothing special, i would be amazed if this was made, trem but with a bit of a twist... and human movement slowed down, and increased or alien movement increased depending on wave difficulty...
Annnyyywayyy i hope something like this is made, this is an awesome idea IMO
NOTE - FOR THOSE WHO ARE ABOUT TO SAY THIS SUCKS, ALL IM ASKING IS THAT THERE IS A SIMPLE AI THAT DOES >> NOT << REQUIRE ANY BUILDING, ANY BUYING, OR ANYTHING EXCEPT "WALK, JUMP, KILL, RELOAD, MOVE AROUND, AIM, AND GO HIDE / HEAL" THEREFORE AI ISNT THAT HARD BECAUSE IT DOESNT REQUIRE SO MUCH TO BE DONE!