I'm a super featherweight and use 16oz gloves on the heavy bag. Over time my punching power will increase correct?
No. Bigger gloves just protect your hand more. I'm a little big bigger than you and I use 14 oz gloves, I still find them too big. You should be able to hit the bag in just hand wraps, granted you aren't using one of those cheap bags that feel like they're packed full of sand.
Only use extra padding if you have sore hands. I do think the 16oz gloves can help a little with conditioning while sparring. Sure they will make you slower, and take the sting a bit off your punch, but they can build muscle stamina.