Diego- my fav PQ modder!
Actually, the game is much more midifiable than all the things you mentioned. It can be modified all the way down to the AI, movement, animation, etc. Modding is scalable- so its appealing to someone that just wants to create a new weapon, or someone that wants to go all out for a TC (total conversion). However, a TC is not going to be for the faint of heart- basically you'll have access to most of the same tools that I used to create the game. Dan provides the "mod code" for me.
Things like weapons can easily be added to the game. The game will launch with about 10 weapons- but it is feasible to have an arsenal of 100 weapons.
Using Blender *might* help you be able to create new models and maps. I don't have Blender loaded, so I can't be sure how effective it will be. We are working on a system that might not require the use of an expensive of difficult-to-learn 3D software. But that isn't definate.
There are indoor scenes. I just don't have any screenshots yet, since I am constantly working on those. Those are among the highest-poly areas, so they need careful consideration. We don't have doors coded yet, but have planned for their use in-game.
Hopefully I can get an indoor screenshot sometime this week.
