This is all theoretical, of course.

Ideally, you'd have Starters capable of going 7 IP every start. You'd need 4 power arms to pitch late innings and two young Starters to pitch in long relief. You could easily get by with just 11 in the 'pen.

I'm voting for having a 40 man roster all year instead of just September. AA would be in nirvana assembling his 20 man bullpen.

Depends on my budget.  If I have a league-median budget, I take option A and spend my money on position players.  Our 2nd catcher is also our DH, and we have a Tony Phillips/Cesar Tovar type to back up everywhere else and to give everyone a rest 10 games a year.  We have a capable CF, middle IF, C and  corner IF in Buffalo.  We do not (obviously) wait for injuries to heal.  If you are ready to go the next day, fine, and if not, it's the 15 day DL for a rest.  We hopefully have two or three starters who can give us league average or better pitching and then we run tandems for the other slots. 

I figure that we probably would lose less than 3 games per year vs. a conventional roster.  Not that I would like this...the diminished flexibility would be damn irritating.