I dont know the Viron, but it seems like it could be an even better kite than the Peaks because of relaunch and same drift?
80 kg and from 10 m/s a 6 will be WAY too big IMO, no matter how little power it has.
A 4 m2 seems like the better choice.
At 78 kg I can not ride my 4 m2 Peak4 above 10 m/s though, thats for sure....
Okay, I can, but survival and not near its sweet spot which is 14-16 knots for me, same type of foilwing as yours.
Regarding line length, I have tried using 15-16 m lines on my 3 m2 Peak4, for quite some time now.
You can still start and ride from maybe 16 knots yes, but even when above 20, carving is crap for me, there is hardly any time to keep the kite pulling and I have to change my whole muscle memory regarding this, and try to carve first and delay the kite, so it pulls all the way around, and still have power on the way to the opposite tack.
Your "working space" gets limited hugely - low end actually close to the same, but overall handling gets really bad IMO.
Maybe it is a matter of riding half a year, and one can get used to it - but I doubt it.
And if so, one also has to change the 4 and 5 and 6 to shorter lines also, as one can not change to a completely different style, whenever you rig one size up or down.
Smaller increments in line lengths might work though.
Peter