I would consider removing
harrow,
grow from the ashes, as well as your
evolving wilds and
terramorphic expanse to make room for more cards. The problem I find with evolving and
terramorphic expanse in two colors, is if you have a good enough land base, they could just be replaced with a basic land so you can still net your turn one spells. The first two ramp spells I mentioned prior do not offer you very much bang for your buck in terms of synergy, you want ramp that can do one of two things: 1. Get your commander out earlier, or 2. Extensively ramp you to your X spells.
Explosive vegetation, as well as
skyshroud claim are both dollar cards and can hard ramp you.
Elvish Mystic,
arbor elf, and
llanowar elves are cents on the dollar, and they're great mana dorks. Perhaps consider adding some hydras, but if you want to go purely another route that suits you, then all the better. Staying at 36 lands is very reasonable for a g/r edh, especially with all the ramp you have, so perhaps aim for that.