When i see a FPS (proffesional or not) i put my attention in two basic things:)
AI
Weapon System.
I think there are seven things perfectly defined to work and i thing the next is the priority order
AI
Weapon System
Phishics and particle system
World , models and characters.
and the story, of course.
Following that, when i see a FPS , the two first things i set my attention are AI and Weapon System.
Many people critics the simplicity of graphics. But i see a good weapon system. With good animations,reloads, etcetera. For example the grenade is excellent.
The AI is basic but works good. At least , the enemys behave difficult to shoot them.
The world design i think is less difficult than the programing. But ever is hard to get a good world designer.
My congratulations.
I think if you get a good world designer and model designer you can integrate a team with the posibilities of make a great game.
P.D. Excuse me for my english. I only speak spanish.