Assuming you are talking impact vest I wouldn't bother -
i guess it is all a personal choice, you can get booties, helmet, gloves but I prefer going out in my boardies
same with fixing stuff, if you are not handy then get a newer kite, if you don't mind spending a few hours putting stuff together then you can buy anything, even leading edge terms fixed for a few bucks
i have a couple of 2006 model kites that still fly like new, have replaced valves and fly them on new bar though
basically the life of a kite can be extended and they are pretty tough
as for leaving them flapping in the breeze I have no idea why anyone would do that, you pump up, ride, deflate in my experience
i have a mate rides switchblades and they are pretty decent steady stabile kites
Ps it's. lot of fun