Not french, but I’ve had some success with the Amerigo which has a fairly short, upswept panel but more flat tree for a more modern warmblood. I have the classic tree, not the Cervia. I like the more forward balance, as I can place the saddle behind his laid back shoulder and still be over his COG. I prefer a narrower twist and this one is comfortable for me. You can get a wool flocked one and have some decent adjustability. My fitter was able to adjust to remove any rock that started once we got some good topline muscle.
Good luck, I can empathize as mine is a tough fit too!