Of course every person who pays for a server can put it to 3 seconds or 3 years because its their damn money!
After playing this game since release and gauging the different modes I would like to give my suggestions for round times.
SA: 25-35 minutes.
Anything below and the one guy who won out early just dominates in the last few minutes. Anything above that and it starts dragging onnnnnnnnnnnnnnnnnnnnnnnnnn; assault spam for 30 minutes is like old 0.3.2, gets painful real quick.
TSA: 30-40 minutes.
Nearly follows the same path as SA, but since its a team its hard to make money sometimes so you don't want everyone stuck in crappy stuff till the last 5 minutes.
On the other hand, its basically the same when it drags on, it really brings tears to my soul when everyone plays through an hour of TSA and there is another hour of TSA up next.
TC: 45-60 minutes, depending on ticket amount.
Rarely is there need of more than an hour, most all rounds are done by then unless only a few people were around to begin with; many of us can remember the pain of TC rounds ending before tickets were up, so none of that.
I've come to these conclusions by witnessing and taking part in collective groans of server wide pain and anguish because some round is dragging on too long or the prospect of some round or other coming up makes people quit. TSA Extremity coming up? A blast for 20 or 30 minutes, but 60 minutes? ughhhhh.
Shorter rounds means less time to catch up if you join late, but it also means roflstomps are over much quicker.
Longer rounds excepting a mighty TC struggle just makes me cry.
Round times being too long or too short is what makes me play less MWLL than I would otherwise.