I think the card advantage from Keranos makes it much more valuable than Assemble the Legion. Assemble can be held off with removal until they draw enchantment hate but Keranos will be netting your cards along the way and doesn't die to Wear // Tear.
If they have enough removal to deal with 1 1/1, then 2 1/1s, then 3 1/1s, then that is card advantage, and Assemble the Legion provides blockers for Tarmgoyfs and Tasigurs that are killing us. Keranos does not.
Decks that you want to bring Legion in against typically run a few copies of Maelstrom Pulse.
Would it be better to leave Batterskull at home? With the rise of Jund and Grixis Delver, you'll be seeing Kolaghan's Command more often. That means tapping out on turn 5 for Batterskull could set you up for a 2-for-1.
I just changed my UWR control to UWR midrange, what do you guys think? Don't really want to use Geist cause it's too expensive, out of stock in my local shop and I find Blade Splicer better with restoration angel. Needs some help with my sideboard too against unknown meta.
Looks decent. I prefer having a 4th Celestial Colonnade instead of a Dragonlord Ojutai. Also, not sure about the playset of Wall of Omens. Often times WUR Midrange is the aggressor. And for the matchups that WUR Midrange is the control player, i.e. Burn, Affinity, Infect, Grixis Delver, I'd much rather have more removal/counters instead of Wall of Omens.