I just wanted to give a different viewpoint on the same horse. I've ridden him twice, and although I event and am not a "Dressage queen," I've run into a few problems with him.
If I take contact with him, normal, light hands but not nonexistent, his chin goes into his chest. There is also a twelve year old girl riding him, and she has very heavy hands. I have a suspicion that her riding does him no good- he does everything to relieve pressure on his mouth, and because he is used to her hands, he does the same with anyone else.
I did find that if I took a light contact and consistently pushed and encouraged him to engage from behind, he would track up and do alright for a bit, but then lack the confidence to continue to carry himself. I think a good term for him would be "nervous and afraid it'll hurt."
On a side note- I jumped him over a small crossrail the second time I rode him, and he came onto the bit and seemed more than happy to stay consistently on the bit when we were jumping. Seems to reinforce my theory that he's used to harsh hands while working on dressage. (The girl who rides him does not jump him.)
I think good exercises for him would be ones that boost his confidence on the flat, and show him that he can carry his head where it belongs and it won't hurt. =] He is a cute little guy.