I may not be too high ranked, only started playing a season ago, but right now damage is very high across the board so tankyness doesn't mean as much. looking at op.gg and your games it looks like a big factor in your losses was your carries weren't doing all that much damage, i think adding a liandries to your build could be a strong help in games where your team is struggling especially with the & hp damage and magic pen coming through, and with your solid kill participation on initiation/tanky junglers your extra damage could be enough to win a teamfight even if the carries aren't carrying hard enough.
Were in a pretty ridiculous meta right now, we've got Galio mid's in pro play building
and then damage items the rest of the way, even saw a few galios with
, and especially for zac as a magic damage dealing manaless jungler liandrys is the best of both worlds w/ a bit of hp a nice chunk of ap penetration and %hp burn.
Obviously i haven't been playing the game as long and all but thats my thoughts on it, good luck man!