1) what tells you that you need more volume than you can get? Is the master up all the way? Are the speakers breaking up? Is the sound just not responding with the punch that you're looking for? I think much of it is my hearing. No, the master is only at roughly 5... no breaking up... and the highs I am missing are likely due to my deafness coupled with proximity of the cabinet. That previous comment was really telling... Never thought of that.
2) what have your bandmates/audience members said? Do they think you need more volume?
Actually no, they are more than happy. The difference in adding the PF500 has been nothing but positive. I should probably listen to them. LOL
3) what does your eq look like, on the amp and on any other preamps (pedals or onboard bass eq)? I play around with it here and there, there is the frequency button, I need to get more acquainted with it quite honestly.
I think there are lots of times when people think they need more but they really just need to make adjustments to what they have. I'm not saying that's the case, but it's worth examining. Very true, you make a stellar point. I tend to over-think and obsess over non-existent or perceived issues. Not doing that would probably save myself a world of headaches.
Also, keep in mind that room acoustics can play a big role. In some rooms, like when my band practices (a basement), if I stand a few feet from my amp, I can barely hear it. But if I move 2 feet to the side (where my guitarist stands), the bass is massive.