I’m 5’11” and a bit and ride a medium. My previous 29er (spesh) was a 19″ but the stand over wasn’t great, which was why I started looking at other options.
I run a 60mm stem and 740mm bars. The stand over is great and given me the extra confidence I needed to try some more techy terrain that I ride.
The reach seems OK, although for mile munching sections I could stretch out more I guess.
As for frame revisions, here is a quote from a recent Cotic email:
Our stock of the different sizes on the Solaris has got a little lop sided, so we need to even it out ahead of new stock coming in a couple of months. Before you ask, there are no changes due on the Solaris on the new shipments!