It could be that you lose a lot of money in 3bet pots when you call a 3bet out of position. 3bet pots out of position are really tough to play.
Also the fact that you like to see showdown can cost you even more money in 3bet pots.
When someone fires 3 barrels in a 3bet pot he almost always has at least Toppair+Good Kicker so is isn't really useful to call with a lot of hands worse than that.
There are special circumstances still where you might want to do a loose call usually when a lot of draws miss and you are out of position.
People tend to bluff the river far more being in position facing a check than being out of position with the initiative.
So general advice: Let go off hands when you face a lot of aggression. There have been discussions made if a herocall is better than a herofold. In my opinion herofolds are better in lower limits because these people are the kind of guys that don't push you around. When they raise they simply have it.
Steals:
Stealing on the Button should be around 50% range. Your sizing on the button shouldn't be bigger than 2,5x.
On the Cutoff you can raise from 2x to 3x. The tighter your range is the higher you should raise preflop.
For example you raise a tight 24% range on the CO: go for 3x.
While if you were to raise something like 33% you should stay really close to 2x.
3betting:
Try to 3bet more in position. For example just 3bet all the suited connectors down to 54s vs UTG and MP in position. When they call they usually have AQ, AK, KQ or something like 77-QQ. So a really defined range that is easy to play against with your 54s.
Versus CO you can obviously call 54s on the button and you dont have to 3bet it.
Versus button you should try to 3bet around 15% in the SB. So thats a lot of Ax suited and a really big range in general. But it is a good range because the Button will fold a lot because of his big range.