I am constantly trying to improve my game and lately i've noticed that im playing way too tight(13/8/2). The main reason for this is because anytime I get dealt a decent hand that I might want to raise some tight player in front of me decides to splash in the pot. This is causing me to muck a hand that I wouldn't mind playing if they weren't in the pot. For example, say a player of 20/6/1 raises in MP and im next to act, when I look down at AQo. Normally, I would either raise or call with this hand given the table conditions, but in this situation I am almost always folding.

My question is, what percent of my opponents hands should I have beat before I decide to either raise or call them? Also, what about if there is a call of the raise already in front of me already?

Thanks,
aytopper