You could always consider craft accessories as a niche... embriodered pin cushions, stitch markers, hand-dyed yarn, etc... that way you can branch out in your crafts, but still be offering 'supplies & crafting accessories'.
From my shopping online and at craft shows, I steer away from booth/shops with too many different items unless there is a clear theme.
It's a touch decision though - I've recently added beaded non-jewlry items to my shop, which are doing well, but do I really want to detract from my jewelry with those items? It's been an interesting experiment, and I imagine that when my supplies have run out for those items I will no longer offer them.
On the plus side, just because you don't sell certain types or crafts doesn't mean you can't still make them for yourself, friends & family!