#1
Adjusting my string height wouldnt bow my neck would it. How can I tell if my neck is bowed or not?
#2
you can tell how bowed it is by fretting the 1st and last on one string and examine to see if the string touches all frets.

and you'd wanna get a new nut for higher strings, otherwise it'll be a bitch to go from low to high frets.
#4
high frets as in 23rd, low as in 3rd. you may be going all over the neck and with the string higher at the bridge and lower at the nut, you`ll have variable action, which would **** you up. and 2-handed tapping would be harder to learn.