firstly, get well soon, and i hope this doesnt put you off mountain boarding
secondly, this highlights a point i always try and make to people, but always get laughed at when i do. In my opinion, snowboard bindings are far safer than freeflexes and other strap bindings, sure, of it gets rough there's no escape, but you know where the boards gonna be when you bail, and thats firmly attached to your feet, not half attached half out meaning you can twist your leg in ways it shouldnt be twisting, and not flying off your feet completely, hitting you in other places (like the back of your head!!!).
But i can see that straps are far better for kite boarding, and i wouldnt even consider using my nosno for kite boarding!!
Another piece of advice i would give is, unless you are doing freestyle, where trainers are useful to allow you to bone out tricks, wear walking boots or some footware which comes over your ankle so stops it from twisting when you bail, my walking boots have defiantly saved my ankles a few times.