I've used french link snaffles, loose rings, and full cheek snaffles. Any suggestions, those don't work?
Don't work how? If it rests in the horse's mouth and doesn't pinch or cause pressure marks then it's working. The thing with a snaffle bit and why it's used in the dressage is because it doesn't put the horse's head down for you, you have to ride properly to achieve a "frame".
"Dressage" means, quite literally, "Training" in French. If you need a big bit to get the horse to listen, there's a problem- and this is coming from a fellow jumper. If a horse won't listen in a snaffle, then you have some major training holes to go back and work through. Get a plain 'ol snaffle and a good trainer, and find out where those holes are, and fix them. Your jumping will be better for it too. Toss the gag and the kimberwick in the dustbin too.
And your horse listens 100% of the time? Must be nice... Are you sure your riding a HORSE?
Not 100%, but 99 is close enough. They all have their moments, they are horses after all. But yes, my horses all go in snaffles. I used to ride with 'big bits' as I said in another thread. The things I've used and done in the past shames me, to be quite honest. I used to think that the bit mattered- it doesn't. The rider, and the training matter. It will be frustrating at first, but the more you learn the more you'll come to find just how much you were relying on those ugly bits, and they are a crutch. Get yourself a good dressage trainer, and learn how to ride your horse back to front in a snaffle.