At NL25 and below, my UTG open range at 6max would look something like 22+, A9s+, A5s-A2s, KTs+, QTs+, JTs, T9s-76s, AJo+, KQo. I think that's around 15-16%. If table conditions require you to tighten up, then fold hands like A2s, 22, 33, 76s, etc. If the table is really fishy and passive, you can add hands like ATo, KJo, K9s, J9s, all suited Aces and sometimes get away with limping (think FR live games).