I love the Dandelion Diamond Rebel offspring. I bred a TB to him an got a wonderful colt that is doing both dressage and eventing in CA with his amateur owner. He is a solid 16.3 out of a small mare, so he can throw his size. My RID mare has had 2 foals by him and both have great temperaments- 1 just started hunting and another just being backed. He is homozygous grey, so foal will be grey
Love Bridon Beale St as posted (even though you said avoid chestnut) If you want similar eventing accomplishments in a bay package, check out Jaunty Star http://www.dkhirishdraughtsporthorses.ca/stallions/
If you like Touch of the Blues lines, but prefer fresh there is a recently imported black stallion is a smaller size (15.3) http://www.stargazeyfarms.com/StargazeysRomanceAtShortNotice/
Bridon Beale St. and my mare are both offspring of Mountain Pearl who produces nice movement and jump with a great amateur temperament. There may still be frozen or his grey son KF Mountain Chieftan
Playland farm breeds many eventers and dressage horses from their RID stallion from Clover Hill lines http://www.playlandequestriancenter.com/PL_Diamond.html
A friend and COTH member has used RIDSH Kings Ransome and been very happy with what he produced http://www.ballytrimirishstud.com/
Another event producer is Braveheart RID http://www.deanfieldfarm.com/