Tanya? LOL. No no, I still prefer the Commando unit from the original C&C and Renegade. Until now, I don't think a female commando wielding dual pistols can take down an entire army of troops, much less fire effectively from such a long range just doesn't make sense. No offense to "Tanya" fans out there.   
All the same, "I got a present for ya!"-Classic commando unit line 

Actually, every C&C game up until Generals has a unit cap... Its a pretty high number, so it was unlikely that anyone would hit it (In RA, it was 20 Tesla Coils IIRC) and its role was to stop a player from congesting the game engine rather than affect overall gameplay.