#1
At about 180 bpm how can you divide it accurately into two, playing a swing rhythm, I try tapping my foot to help but im not John Bonham, my foot cant keep it up.
#3
are you trying to play swing? or are you saying it just sorta happens by accident when you go that fast?
#4
If the fastest you are going is 8ths at 180, then do 1a&e - 2a&e - ect(16ths) at 90 BPM. That puts less strain on your foot. =)

Timing is all about practice though. Just work on hitting perfectly timed 8th notes at 100 BPM and then keep bumping it up until it's second nature.