The XO (crossover) and the LPF (low pass filter) are different settings. It is an absolute must when using room correction to not have the LPF on the Sub and the XO set by the AVR overlapping (hence the instruction to set the Sub LPF to Max/Bypass/Off: it is very undesirable to have any stacking of Bass Management between Sub and AVR).
For the actual XO between Sub and Speaker in the AVR, it is generally recommended to start at 80Hz. Another point of guidance is that you set the XO 1/2 octave above the Speaker's F3, yet another is 1 octave above the Speaker's F3. In all instances it is advisable to listen and experiment some.
Many find that a higher XO usually allows the Speaker's Mids and Highs to be more clear and punchy as the most energy demanding Bass rolled off to the Sub. For my experience with an F3 at 25 Hz or 34Hz, I had still kept an 80Hz XO because of that clarity and punch I described. Everybody is a little different and I know some folk here have selected higher XO points of 100 or even 110Hz.
120Hz is the point where pretty much everybody agrees that you can begin to localize the Sub (meaning that you can identify that the sound is emanating from the Sub, rather than blending with your Mains.
There is another setting you will likely have in your AVR which will dictate the LPF of LFE. This is specifically for the LFE channel in multichannel programming and it should always be set at 120Hz.
What you describe with your trims looks good.
@OldAndSlowDev : what Distance/Delay did the AVR set for your Subs?