Table selection/stack size and SPR related question

[rh2020]

When you have built up a decent stack i.e. >3BI. It's often easier to be the bully (it seems that way for me partly due to confidence). If the table gets a bit dry in terms of action, or the VPIP drops down below say 20, do you change tables? Even though you have the big stack aggressor advantage?

Sometimes I find it difficult to discipline myself in this position not to call too often as it's a small portion of my stack.

Which leads nicely on to SPR. Would also be interested in seeing some thoughts (or threads) on SPR as it's not a concept I'm too familiar with. i.e. as your stack grows in size, how does this affect your decision to call.

I've read some interesting comments by Jeff on particular hands relating to SPR but wonder if there are any more general threads around?