Optimal Orbi RBR50 & RBS50 set up?

I just moved into a new house and am trying to optimize the positioning of my Orbi equipment.  I have one Orbi RBR50, two RBS50s, one RBS20.  I also discovered the previous owner left two Luxul XAP-1510 wireless access points.  The wireless specs on these look faster than the Orbi's.  The house is two (tall) stories, 7500 sqft, roughly in the shape of an L.  The Orbi router is on the 2nd floor roughly in the corner of the L where internet comes in to the house.  Ethernet is available directly below the Orbi router, anywhere in the attic, and in an office that is on the opposite side of the house from the router.

I'm looking for suggestions for how to optimize the positioning of all this equipment, as well as what settings to use for the channels of the Luxul equipment vs. the Orbi equipment - should they operate on the same channel?

There is not much interference from neighbors.

Thanks for any suggestions!