I see some of the usual suspects have chimed in here
I run Nissa instead of Yeva, but there's a teensy bit of overlap, and I've had my list together for quite a while now. There's a few bits and pieces I can potentially recommend.
As
@OCPunisher mentioned,
Cloudstone Curio can potentially just be disgustingly good here. You seem to have a lot of ETB triggers to play out, so it's a strong card, as is
Wirewood Symbiote, and as
@weltkrieg mentioned,
Temur Sabertooth. If you want to go further down that road you could look at
Panharmonicon too. It's...uh, pretty devastating.
I'm also going to second
Beast Whisperer. You really don't care that
Primordial Sage is bigger, you really just want the draw triggers sooner, and BW does that, no muss no fuss.
Besides, you also have Soul of the Harvest which triggers off of tokens - Sage doesn't. edit - my bad!
Some of the more value-laden fatties in my Nissa build are
Woodland Bellower and
Pathbreaker Ibex. The first gets you whatever you like - ramp, draw,
extra lands, a
manland if you run it. It's just really great value. One of my favourite things to do is fetch
Fierce Empath to set myself up with a board state answer, like
Thorn Mammoth or
Pathbreaker Ibex. The second, well, Ibex is a finisher. I have a bit of finagling around making it work, but your guys have flash, so you've got an army in a can whenever you like. Seems like a good deal to me!
Can I also suggest
Seasons Past in place of
Greenwarden of Murasa? Self-exiling means you get one shot at extra value, whereas SP beats that for value any time you cast it, and you could well see it again, whereas you can be absolutely certain you won't with Greenwarden.
I'll also second the land thought that
@weltkrieg mentioned. I also really love
Wave of Vitriol. Too many people sleep on that card, it's just damn excellent. But you probably need a few more basics to make its symmetry favour you. There's a few lands in your list that probably aren't desperately needed - Okina, Oran-Rief, Cabin,
Temple of the False God, and such. You'd be better off with basics, knowing that you can cast Vitriol and be the only one who's colour and utility fixing isn't wrecked.