10-speed or 11-speed seems to be the most pressing decision with this build. I have a bunch of great old Dura-Ace 10 speed stuff, and I run 10 speed on my smart trainer. I have a Sram Rival 11-speed FD and RD that I just removed from my CX bike when I went 1x on it, but I have no shifters.
So, I have elected to stick with 10-speed, as the cost of Sram shifters and a new cassette for the smart trainer is just too much right now. Using the Dura-Ace stuff means I need to spend $40 on a new clamp on Shimano 105 FD, and I am all set.
Here's a look at the Dura-Ace goodness while we wait for the 105 FD to arrive.