My big suggestion would be to put real deal effort into moving without the ball. A lot of times, I can start with a foot in the paint, perform a light jab, then pop out to get the ball, at which point I can size up my defender and make my move. A lot of times that's enough.
However, like you, there's other times where I'm playing against a defender who's bigger than me and of similar quickness and at that point, a simple jab and pop doesn't really get me anywhere. I may receive a pass on the wing, but the defender more or less had to take two medium-effort steps outward to re-establish his defensive position.
As such, what I like to do in those situations is put my defender on the run. Unfortunately for us, that means we have to put forth the effort to go on the run too. Instead of making a lame jab into the lane before popping out, maybe take two or three fast steps in one direction then jab and head to the other wing, anything that'll force your defender's movements to become a little more urgent.
This way, instead of that fellow waiting for you in perfect position by the time you receive the pass, he may be a little more alert. If you work it right, your quick jabs, cuts, and pops off the ball may lead to a fast pass and reception before the defender's truly set, which leaves him susceptible to responding to your moves before he's ready.
It's like this, if I'm normally sizing up my big defensive opponent and I pump faked, he'd kind of respect but his balance would be solid enough that he wouldn't have to totally commit to contesting. But suddenly, if I've got him chasing and I throw that pump fake before he's set, there's a much better chance his counter-move will not be as effective or balanced.
I think this Dell Curry video is a great example of the simplistic benefits to truly running, moving, and cutting to get open, as opposed to just popping and squaring up. Chances are, had he been standing still and facing up Michael Curry or Cliff Robinson, Dell wouldn't have been breaking those fellows down. But once he was on the move, they were at the mercy of his ball fakes and quick releases. The first two shots are just great catch-and-shoots, but the third play is pretty close to what I was talking about