I carry 24 players on my Double A & Triple teams (12 position, 12 pitchers) then I put 2 extra pitchers, usually relief, who are also on my 40-man, I put them on my Single A team. Then I use those 2 for shuttling back and forth onto my big league squad to keep all my arms fresh.
I'll never be guilty of under-using optioning players back & forth, back & forth, from majors to minors, during the season. I usually use 3 & 4 relief pitchers that I constantly shuttle between levels to eat up innings for when my starter bombs. So basically I have a 27 man roster instead of 25
I now try to carry 45 pitchers & 45 position players instead of the 46 or 47 position players I use to carry.
My personal setup/breakdown
MLB - 13 pos., 12 pitchers
AAA & AA - 12 pos., 12 pitchers (4 outfielders)
Single A - 8 pos., 9 pitchers
EDIT: as for the OP, I wish for 19 ai wuld do this for other teams as well