First up, I’d expect the tengu first before pretty much anything else to be the next playable if there will be simply since they have the most potential to be.
As for the Skritt, it’d seem fairly easy to overcome their intelligence issue with technology, which they’d be able to solve if you got enough of them together eventually. Perhaps they invent some apparatus that transmits their strange little growl signals over a vast distance. This would allow them to actually venture out without becoming dumb as a brick.
Of course I may be misunderstanding how their intelligence works, please correct if so.
Edit: I missed the post a little above with essentially the same idea.