Thanks for your replies, I really appreciate the knowledge.
I tried changing the auto settings and adjusted manually the way you mentioned but I still find myself having to adjust on the fly because the bass gets too boomy. The way I perceive my issue is that because my preouts lack the proper voltage for my mc8207 I have to increase the volume/gain more. By doing so the subwoofer volume/gain goes up disproportionately to the speakers. Does that make sense? I might be totally wrong...
That and my wife always complaining the dialogue is too low lol.
Setting up can be a long and frustrating process.
And there is no standard for sound levels. Some contents have low dialogue levels, some have high. Some contents have low bass level, some have high. There is no way to have one perfect setting for all contents.
Just know that it is all in the setup.
If you feel the bass is USUALLY too much, then reduce the subwoofer levels more and more until it is not too much. It balancing act among the levels.
Experiment. Like set FR, FL, SR, SL to +3.0. Set Center to +7.0. Set the Atmos ceiling speaker levels to +10.0.
For the sub level, play your favorite song that has good bass - like Eagles Hotel California Hell Freezes Over. Then adjust the Subs up or down until the bass sound about right to you.
Eventually you will get a good feel for the best sound. It takes experience. Takes time. Not overnight.
With my CX-A5100/MX-A5000/AT2005, the ONLY thing I usually change is the Master Volume.