Realistic thingy will screw up the gameplay's balance etc.
The woman one was never intended to be made. It was an April Fool's joke. Besides, I don't think MM supports it.
Water sounds are interesting, but it could cause a need to change the format of the map.
Explosive polys are well-liked and popular, though it'd also cause a need to change the format of the map.
Lobby chat is coming up in 1.5. The weapon.ini suggestions are always good. Widescreen sounds good.