Overall I really like it. I think that there are a few small changes tha you could make but on the whole the theme is solid.

Striaght out, you need a Fauna Shaman / Survival of the Fittest / both. Considering that Champion of Lambholt / Craterhoof Behemoth are your primay win conditions, you need a consistent way of fetching them.

Your counterspell suite needs a bit of work as well. Arcane Denial, Muddle the Mixture and possible Dispel should be in here. they help keep Edric alive.

The other stuff I would include is Priest of Titania to help get your craterhoof down since you have a lot of elves. You could also look at running Elvish Archdruid as he gives an anthem too.

You should be running Sylvan Library and possibly Mystic Remora. It's important to have early game card advantage seperate to your commander and there two can be super aggressive. Remora is good in that it either slows your opponent down or feeds you cards. Both choices are good. You don't play it turn 1 but a turn 3 play is solid. Then just pay the upkeep once or maybe twice and ditch it once you have gotten value.

You don't need to be running Spellbook, it's waste of a card here. even if you're limited to 7 cards, just pick the 7 best.

So having a look over the list again, the things I notice the most are:

• you're relying almost entirely on Edric for card advantage. While you can lean heavily on him, I still think it's worth including additional support. You have Sylvan Library but I would recommend adding Mystic Remora. You should also be running Green Sun's Zenith. You could also consider Glimpse of Nature.

• You don't have many ways at all of buffing your creatures. Most of the time they'll only be 1/1s. I would recommend adding a Nissa, Voice of Zendikar to help with this. You could easily replace Essence Warden with it. I don't think warden is very good here.

• You don't have a fallback if your board gets wiped. You could spend all this time spewing out creatures and one good wrath can leave you with no board state and potentially no hand. I would recommend adding a Creeping Renaissance to the deck. It lets you bounce back after a wrath. Mystical Tutor is good too - it gets it as well as stuff like Notorious Throng.

also, of the cards in your maybeboard I think are worth getting 9specifically for this deck):

Arcane Denial, Botanical Sanctum, Breeding Pool, City of Brass, Fauna Shaman, Force of Will, Gemstone Caverns, Mana Confluence, Spell Pierce and Survival of the Fittest.

There are others too (like Mana Crypt which is always good) but Those are the ones I would be trying the hardest to make space for.