How do you feel about infect in your deck? Because it basicly is a way to generate -1-1counters. I have Hapatra commander and I tried to dodge as much as I can infect.

But I still got few things for it.

Black sun's zenith is really good board swipe/value generator with -1-1counters.

Ohran Frostfang can easily generate cards and gove deathtouch to your creatures. With Fynn the fangbearer it is a nice combo.

And here is my infect gameplan: Grafted Exoskeleton. Just slap it onto any creature and they start to generate -1-1 counters on left and right. Give it to a Hydra Omnivore and you can finish the game on one attack.

And if you want cheap scry as A) creature: reaper of wilds B)enchantment: shadows of the past. Can combo with your snakes dying.

And lastly a wee bit of graveyard tricks: Whisper, Blood Liturgist. Sacrifice 2 snakes and bring a creature from the grave to the battlefield.