I know when we faced the Gold Coast Hurricane's 12u team in Myrtle Beach last year they carried 15 or 16 players and 5 were pitchers. I thought that looked like a parent nightmare and wondered how that worked for them.
Depends if you are a parent of a player who plays or a parent of the ones who don't. A lot of these marquee teams and programs not only carry large rosters, but they also tend to pick up players and replace you in a second.
I much prefer to carry 10 or 11 and have a great relationship/reputation with all the other coaches and players so when I do need guest players then it is not too hard to get them. If we were playing full regulation games all the time where there is a lot of opportunities to sub in and out players then I would want more, but we don't.
And if you think ASA Qualifiers don't allow guest players then you are dreaming. A blind eye gets turned all the time or there is 'special permission' or whatever.