/vr/ - Retro Games

Hey doomfriends.
I've had an idea for a fps I want to prototype, and thought about using one of the many doom source ports to do so.
How "creative" can I get with doom modding? I'm aware of many mods that are more than just reskins, and also I know some of the engine limitations (like no rooms on top of other rooms), but I'm unsure on what can be done with scripting. Or how hard it is to move away from the default doom