I am at a much better place. I took the mixture screw out to 2 1/2 turns, tightened the advancer springs, and advanced the timing just a tad, and now it starts flawlessly runs super well revs up and back down well. the only small problem left is that I can't use the throttle too quickly, if say from idle I wanted to use 1/3 of the throttle instantly I could do that but not more than that.
You've made a good improvement with just a few tweaks, so I would recommend that you keep tinkering with it and learning what it wants. 
Edit: From my limited understanding the mixture screw only affects the mixture for part of the rev range, so is there a way to check to make sure the mixture is good for all of the rev range?
The different carburetor circuits are controlled by the amount of throttle opening, rather than RPM. The mixture screw is for idle, and has a slight effect at small throttle openings, where the slow or pilot jet takes over up to 1/4 throttle or so, when the needle comes into play. The needle's influence tapers off at around 3/4 throttle, where the main jet comes into play up to full throttle. All circuits have some overlap. Simple, right?
I agree with this. When I got mine back on the road, I fiddled with needle height, but had to take it back to original position, to get it happy. I resolved 95% of the rapid, hard-on-the-throttle hesitation just through mixture screw adjustment, very careful points set up and new plugs.
Initially, I was adjusting the mixture screw too much each time. 1/16th adjustments were what was required. I think the idle/pilot circuit has more influence on the initial response to WOT than we give it credit. That's where I'd concentrate. 2 1/2 turns out is a long way off the stock position of 1 turn (that's the 750K6 stock setting though). Possibly gone from too rich to too lean? Just tweak the screw, get the bike warmed through, few miles of spirited riding and check the plugs. Adjust. Go again. Took me about half dozen rides to get close. I probably checked my plugs a few times afterwards and no longer think about it for the last 2 years /4,000 miles.
When I say I resolved 95% of the hesitation, I never feel it on a run, even when I grab a handful for an overtake. I can tell it's there when I whip on the throttle from no throttle to full, standing on my drive. I suspect that's not something I can do anything about, nor does it matter to me.
