Yeah.. I understand the "don't distort actual play" thing really well (heck I've written articles about terrible Achievements before), but honestly I think the "gameplay warping" thing is so minor to be negligible with most of these so far here.
In general, if someone chooses to hurt their chances to win an online match to get an Achievement, then it's on them really anyway. Otherwise most of these would just happen anyway naturally really over time... well, maybe not Time Out or the Midori or Rook ones, those could be a bit iffy
But yeah, getting wins / doing good stuff in 1P modes type of Achievements are all that's really needed anyway.