Are the slicks new as in last few months or new and been sitting for awhile ?
Have you tried to footbrake it up to around 2500 and then let it rip in the burnout ? This was always the fix to the old rattling 2032 gy's . I think wheel speed and conv is all of your issues, conv is a lot tighter then it should be, it'll help issues down low and make it more consistent down track. But I think you can help your cause with the 4:30.
Do you run 1/8th or 1/4 all the time ? I see one local car chirp the tires the entire way down the track here been doing it for years.