As one who's made a few Infinity and 3rd party maps before, I've just come from playing the first level and the first part of the next. The level design and texturing looks good so far. I like how you put in secrets right from the start (won't spoil it).
Music is good. As for using existing assets; if the creators don't have a problem, I don't.
Glad you haven't thrown endless perpetually respawning Pfhor at the player; I tossed a scenario into the trash for doing that number on me.
Only suggestion so far is that the environment outdoor lighting (and shadowing) could be a little more detailed.
Its nice to play fun levels, and so far Phoenix has them!
Glad to see that among any of Tim's texture enhancements are those also done by volunteers for the old A1 Texture Enhancement Project. I contributed some through Jesse Simko several years ago; the water set door texture was my favorite.
These are fun to see in game now that A1 is much more fully developed.
Keep up the good work.