17 is a lot of cards to cut. So I'll give some general advice on cutting cards, rather than giving some specific examples.
First is to decide why each card is in the deck. You have already divided your deck into categories. This is a really good start. Most categories are going to have three to ten cards in them. Your "Aggro" and "Utility" categories have 17 cards in them. That's a lot. I would suggest that is where you make some cuts.
Also, decide on a
game plan. How do you want this deck to win? Only keep the cards that further that goal.
Your "Ramp" category is also huge. You'll want to cut down some of this. If all you draw are your ramp cards, you'll have nothing to do with all that mana.
36 lands
might be to much. It is an Omnath deck, so maybe not. Personally, I would cut a couple. Particularly
Dryad Arbor. I'm in the "
Dryad Arbor is overrated" camp. Unless you are doing graveyard
shenanigans with it, it is generally inferior to a basic
forest.