I also have an, ahem, communicative, chestnut mare. They will teach you a lot! A few things I have noted:
-mine likes to be groomed/touched more gently
-her “volume” reflects the “volume” of the people around her. She does not like “loud” people.
-She does try to “speak out” about things she does not like, and sometimes that’s not acceptable. When I first started her, she was absolutely perfect to mount, but she HATED when I dismounted, she threatened to bite me. I know for sure she wasn’t in pain, so once or two appropriately timed uses of the dressage whip helped. Once or twice since then she thought about being cranky and all you have to do is look at her and the impulse goes away 
-this mare is very happy to be on year-round regumate
-maresy LOVED being preggo 
I am glad to hear you are investigating further repo issue, I’ll be curious to hear what you find!
