i think it's quite a good team.
you're right that your 3B position is a weak point. i would guess in a small league like an 8 teamer cantu's lack of production for a 3B is especially pronounced.
i also think your starting pitching could possibly be a weak point as well. you got great consistent starters in johan and roger, but myers could possibly - and schilling probably definitely - mess up a playoff week. felix is a great starter like johan and roger, but i think he could have a blow up any start now.
overall though, good team. i don't say spectacular only because some of the other teams also probably have great lineups like that too in an 8 team league.