Just look at a tower thats already marketed and see how tall it is, probably your best way to do some research... also the guy woudl probably be able to fabricate you somethign really sweet if you gave him some ideas from other towers
as far as i know, to a certain extent anyways, as high as the tower is will somewhat affect how high you are.....but more air equals more pain....my tower is 7.5 from the floor of the boat and i think that may be a few inches higher than the average
How do you get up there? Without hurting it or yourself? I bet riding behind that thing would be like riding on the cable except you'd have a wake to work with, I bet that would be sweet! But I bet its also a royal pain in the arse to take care of.
Nearly all towers and pylons have a tow point height above the floor of 7'. The tow point would be 5' if you mounted it on your gararge floor but most boat gunwales are about 2' above the floor of the boat.
It if it was much lower there would be a lot of head banging, much higher and you would need a step stool to get to the rope.