Just wait for the ban hammer. If anyone in your meta is playing it then don't play. The deck is just that unfair in my opinion. I saw a guy Thursday play 3 mimics turn 1 and reality smasher turn 2 with simian spirit guide.
Going forward I feel that aether vial will be more important as we are going to be sacrificing lands like there's no tomorrow with the surge of tron and eldrazi. I think that beast within will be a great sideboard card for those decks.
I would have some number of kitchen finks and voice of resurgence on me as I'd expect path to not be played as much. Qasali Pridemage would probably be another mvp to have around. With so many multi colored creatures I would play wilt leaf liege along side elspeth, knight errant as my curve toppers.
I like your list but I feel you could use a land or two and cut a colorless source for another thicket. Maybe, try elspeth knight errant instead of sigarda. The old elspeth + mirran crusader synergy seems good right now
I ran a build with 4 of each Thorn of amethyst, Vryn wingmare and Thalia the Guardian of Thraben. It's pretty cool to watch your opponent fumble to remove them all especially if you play them in succession. Starting off with Thorn puts the hurting on their tempo as its harder to remove.
I've been thinking about using advent of the wurm as a pseudo siege rhino while staying in color but I'm fearing getting blown out by vapor snag and other bounce effects. The 5/5 trample body along with exalted triggers seems like a good way to close games.