I'm a bit stuck.

I've got a Olympus E-510 bout it with the dual lens kit 3 years ago in NY (wanted a dslr & it was a good deal when the exchange rate was 2:1)

I've got a full set of filters (about 30 of them, almost anything you can think of) & a stand (cheap but holds the camera) but feel like I should treat myself to some new bits (a new camera is out of the equation)

You can't buy talent but I'm getting better. The camera is used when I go to weddings, parties, anytime I have to visit the inlaws (I get bored easily) & general use.

I'm thinking of a proper flash (for indoor stuff) or a battery grip (to make it feel a bit more substantial, I'm 6'7" and it feels a bit small). New glass is tempting but now sure what I'd get, I don't do macro work (bar ebay photos of cpus) & don't do big zoon atuff (although a bit more zoom would be nice)

Any ideas?

A better tripod and head?
New bag?
Nice prime lens?

I hardly use a tripod
Bag's fine

Prime lens, hmmn (drools a bit), might be a bit too pricey but am now googling

Battery grip is nice if you do a lot of portrait orientation pics. A prime would be nice too.