Just wanted to type a few things (relevant or not LOL)
The not sure part:
If the kite needs a big leading edge to provide that slow and stable feel like another famous AS kite has it will need to be 5 lines. I’ve found from riding the other famous kite that when that large LE hits the water you almost always need to do a 5th line launch.
The part I'm sure about:
Also I personally find and know that the 5th line helps first distribute the weight when flying thus less shape distortion creating longer flights. I think the big LE also helps in this regard. Also in high wind you can see the tension on this powered 5th stopping the kite from drifting back and causing unwanted drag like a 4 line kite does. As I have both AS kites 4 and 5 line its clear to see the 5 line out preforms the 4 line hands down without question.
If this new kite was a 5 line with good load distribution I think this would help the kite excel in the AS area.
As for the rear settings I like the three fast, med, slow. Or if I’m really hung-over at the beach I find those little rabbet /turtle pictures work well too.