Personally, it looks to me like she isn't in a true frame. Especially if you have that strong of a bit with that much leverage to get her to give to the bit. Her head is in, but she is not level with her withers or even slightly above. Unless you are asking for that high of a headset. I think you should try using a french link snaffle and lots of leg..and I mean LOTS to really get her moving forward into the bit, and play around with it a little (the bit that is, wiggle your hands so she knows its there), its taken me a year messing around with my horse and trying different things, but that is the kind of bit he goes in and he has been absolutely wonderful with his head carriage the last week with no side reins, draw reins or any kind of gadgets :)
(all this is coming from a hunter rider on the VHSA curcuit, so if you ride "wenglish" or something else, you may want to disregard this)