Title speaks for itself, I think. You’ve been looking for ways to make Karma matter, here’s one way to do it.
Same way Legendaries currently work: right-click, choose a new set of stats.
Consider that high-level players will probably want to switch often when doing different dungeons/WvW events. Plus, newer players might like it a lot more than looking through Trading Post listings for improvements to their build.
Suggestion. Thread. There you go.