Javid, that statement coming from a soldier is particularly disturbing O_o
Anyway - a couple of ideas for a possible Counterstrike: Black Mesa:
All maps would represent parts of the Black Mesa Compound.
In the Hostage maps, the counterterrorists play as the BM Security Force, trying to rescue Scientists from HECU Marines.
In the Defusion Maps, the counterterrorists play as HECU Marines trying to prevent Black Ops from blowing up a tactical nuke warhead.
The VIP maps feature Security Forces again, escorting a scientist in an HEV suit to a Xen Portal (mapping based on Lambda complex design), and Black Ops trying to stop them.
Weapons would be based on those from Black Mesa and Opposing Force, including the HD variants as standalone versions with different firepower and accuracy.
Weaponry:
Pistols would include a Glock, Beretta, Magnum and Deagle.
Primary weapons could be the MP5, M4 (more firepower, more accuracy), SPAS-12 shotgun, M249 (from Op4), or crossbow and M24 (from Op4) for snipers. Melee weapons would either be a crowbar (for security forces) or combat knife (for military forces).
Grenades would be the same as in Counterstrike.
Additional weapons could be incorporated for more variety, but I don’t think they’d be needed. The game would be pretty fun all the same. I think in Counterstrike: Source, most players also tend to use Mp5, M4 or M249 most of the time. But I could be mistaken, it has been a while since I played it.