Did you ever think Half-Life was way too easy? Hard-Life corrects that issue.
I was not happy with the previous w_rpg, I went over-simple and it looked like a big turd. I think this is a happy medium! Some extra chaff to make it look more like an RPG, but the same simple textures and accessories to keep it grounded.
Gabe, call me.
I think you could replace some stationary gun grunts in On a Rail with rpg grunts to spice things a bit.