I have no recent (mainline) experience because I’ve been buying F or J. BUT…My experience flying in exit rows on CR2’s is that the seat next to me is usually the first seat to get assigned at the gate, with seats in the back being the last to be assigned. And, I am often the only one who boards when they call GS and 1K at the same time.
Thankfully UA has swapped out CR2’s for CRJ550’s on the ORD-AVP route.