Current thinking seems to put optimal cadence in the 120-130rpm region. Aiming for 140 is too high. Based on what you've written, you should at least be doing your F200 in 51/13. Unless this competition is critical, then I would actually go 52 or 53/13. You are going faster on bigger gears and showing good adaptation. A couple of weeks ago, I personally ran 12.06 in 51/12. Not too bad, not too good, but when you consider I'm at 130kg and a sail at 6'5" and no disc, it's pretty damn good. The beauty about bigger gears is that the tapering off of speed is much less at the end of your run.
For the run in, I have a friend who has played around with this a bit, and he has very little difference in F200 times by jumping in T3, or even waiting until coming out of T4, so I don't think that is as critical as some might think. As far as speeds go, guys that do low 11s are looking at the final run down the back straight to be at 45-50kph. Whatever you do, power up the banking into T3 to reduce that drop off in speed while in the saddle and get on the gas somewhere in T3-T4. The correct line is really track dependent so watch what your really fast guys do.
For the windup, the common school of thought is a slow path to the fence in the last lap before the fly. My mate has been fooling around with this and has been going straight to the fence from the start. I've tried this and it works well for me too. The slow windup means you're constantly on the gas. For me, straight to the fence means you get a little recovery running down the banking onto the straights. I'm fit enough to recover very quickly, so I think that is why it works well for me. Whichever way you look at it, studies show that the fastest people are the ones who use the least amount of energy in the windup. It's just something you have to work out for yourself.