you are awesome. keep up the good work.
i'll probably donate again at some point just to support your efforts.
this is some very useful stuff for us retro fpsers!
some ideas for future stuff:
thematic levels, like you have doomish techbase now, you are gonna have outdoor textures, how about some doomish gothic hell type level textures, a toxic waste type facility level textures, stuff like that. you could reuse alot of the stuff you already have for wall textures, just recolor them and modify details.