I dont know if my input is any good here, but something that may be of use to you i hope.
One of the things I've started doing is relaxing my inside shoulder going into a corner; letting the shoulder drop to the inside, along with the elbow (i havnt got the full technique understood yet, so I might be wrong). This makes the bike feel more settled, feel less like the front is going to wash out mid turn.
Hope it helps. As for the dilema about braking and when to change gears, I change down as I brake, using the engine braking to help me - I like to be off the brakes just before I turn in and roll in on the engine braking, using the throttle then to steady the bike and keep the weight neutrally distibuted
Anyway, I think what others have said is probably more use, but I just wanted to share what I have found out
Matt