In my experience (enthusiastic amature - Canon A2E, Canon S35 (predecessor to the S50), Canon 10D), I was never able to get really satisfying indoor shots with any built-in flash. That's because I really don't care for the inevitable 'head shadow ring' effect. As soon as I stepped up to an external flash (hot shoe type), I was sold. Bounce flash, diffuser, range, less red-eye, flash exposure readings... it's no comparison. My advice is to try a compact P&S that has a hot-shoe and use an external flash unit (the G5 and its predecessors have one) for those times you need it. 400 should be plenty of ISO range with a good flash. This eliminates the smallest P&S cameras, but the G5 isn't that big.

-Zeke