"Zip line feature?" So the tow rope slides back and forth a few feet across the top bar?
Might want to get some riders to test that one out first.
I remember the old outboard tow system where there was a cable that attached to the transom tie-downs and a the tow point was on a pulley that would slide side-to-side behind the motor. I never liked it much on a slalom ski.
Other than personal opinions on looks, the sliding tow point might be the biggest issue.