Have you thought of reducing the gear ratio on your final drive?
For instance 9 or 10 teeth at the front in stead of 11 and 44 teeth on the rear in stead of say 41 or 42?
And learn to mostly control your speed with the rear brake, instead of the clutch, at very slow sections, in other words learn to be sensitive with your right foot.
Something else that might interest you: I've adjusted the idle speed on my 4RT reasonably high, at about 1100 to 1200 rpm and I can put the front wheel against a tree with the bike in first gear and it won't stall.
(this is of course without my weight on the bike)
Although the idle speed is reasonable high, I can ride very slow only using my rear brake... (this also reduces engine braking as feared by most 2-stroke fanatics