The curse of being good at limited is that everyone malds at you at every opportunity.
It's... very rigid. The color-fixing is great, but it is 100% a synergy set. Meaning that if you splash, ideally you want that third color to be part of a shard or wedge that is part of the same game-plan -- abzan, for example, is pretty great because GB cares about 1/1 counters and GW cares about modified, with WB as some weirdass inbetween. Temur by contrast is a little too over-the-place. GR and UG love eldrazi, but UR loves energy.
The big issue is RB. Removal is stupidly important in the format because there's so many cards that just pop off if unanswered, and the eldrazi-ramp decks need to have their early ramp interacted with. Red has some of the best early-game removal and black has great unconditional removal, but the big issue is that... affinity fucking sucks. It's garbage. It can support one drafter, maybe, per pod - but even then I'm skeptical.
Honestly, I think Thunder Junction will be remembered as the better format, but the sheer ease of which you can ramp to 7 mana in this format is pretty instructive for making expensive cards matter. Seriously, the Eldrazi Decks pack a punch. That stupid GR 2/3 reach for 4 that makes 2 spawns on cast is one of the best commons in the format bar none.