This engine is cool, and should be noted that this engine will be the recommended software quake engine for future versions of Hellsmash.
Some feature suggestions for future versions of this engine:
Weaponmodel -
cl_mirrorweap (or whatever the DP version is) - mirrors weapon model left / right (as a cvar, then code could be made to properly align projectiles)
Sound -
Addition of some new ATTN_ functions as detailed below would be nice:
ATTN_SELF - Plays the sound for the entity emitting the sound, and ONLY the entity emitting the sound. (only useful for clients, but very useful nonetheless.)
ATTN_MUFFLED - Plays a sound muffled. This would also be recommended to automatically happen for sounds occuring in liquids. (i.e. it's very strange for explosions that happen underwater to sound the same as explosions in open air.

)
ATTN_DAMPENED - Volume fixed at 1.0 for the entity emitting the sound, for other entities, the volume is set using the volume field. Good for soundproofed rooms, power suits, gasmasks, etc.
ATTN_FOLLOW - WHEE rocket flyby whooshing!
Centerprint -
Bug - Too many \n's or wall of text results in wierdness in the status bar. (gets overwritten / blanked or something)
This only affects the old status bar, and happens in vanilla winquake too.