just to field some whacky ideas

Light and experimental class aircraft in the US have been using ballistic parachutes for some years. Some of these systems are deployed by a simple spring loaded mortar, or more intensive CO2 system. The purpose of the mortar is to deply the chute clear of the aircraft. Chutes themselves are sized to the all up weight of the aircraft/fuel/occupants but some companies are making systems for flying drone copters, just for safety as these machines and their cameras can be expensive.

Single line kites usually have a tail for stability, yet I notice all the surf kites are multi line and tailess. I think the easiest to launch are similar to rogallo wings once fielded by NASA and which were among the first hang glider types, but more power is gained from two line bow kites or parafoil systems as they have wing span. Bow kites themselves have some form before liftoff as the soft bow holds the shape.

I guess the advantage of a proa is you can launch behind the boat, then reverse direction easily after the kites deployed and safely airborne, with the boat off into the intended direction.