As sad as it would make me to do it, I think I am going to dismantle Go-Shintai for the time being and give the enchantment-matters guts to Myrkul. I'm not sure that I have quite all of the pieces I'd need to get Myrkul to work (notably, no Oracle of Nectars at present), but the pieces keep coming together. (I mean, I got a Devoted Druid from the List in a MOM booster. Crazy!)


I'll keep Go-Shintai together for right now and then when there are a few more pieces in place I'll give Myrkul a run-out.

Pulled Mirror Gallery and Mirror Box out of this list - while it seems nice to have Mirrormade come in as like another GSoLO or something it's not worth the two slots, particularly when Mirror Gallery might literally not have any other use here. Oh well. Put in a couple of Fiend Hunter-style things in enchantment form in their place. 
Sphere of Safety would be a good add here for sure, although it's awfully pillowfort-y. 
Wrenn/Nissa/Kiora would be good adds as well. Those would be my preferences, I think. 
I'd probably have to fire up Forge and see what cards I had in the uber-ridiculous-who-cares-what-it-costs version and figure out what would be the nicest bit of bling. I know that Reshape the Earth would be pretty solid; having a way to accelerate the Maze's End win seems like a decent plan. 
Amulet of Vigor would be helpful but probably not as much as I think - Gond Gate fixes a lot of that problem.
The last time I played this it ran out of gas hard; I was begging my deck to give me a blue shrine and just didn't get one. The other possibility would be an Enchantress effect; there are quite a few card-drawing effects in here but the deck grinds to a halt if I can't find one.

Just thinking of Oblivion Ring, Prayer of Binding, Prison Realm, etc. Probably Ghostly Prison/Propaganda style effects would be good to toss in - Sphere of Safety is a big win here.

BNG Kiora, OG Garruk, ZNR Nissa, DOM Teferi, MID Wrenn, and M19 Vivien (kind of) all seem like they'd be useful. Adding them to the scratchpad.