Need help with WiFi Mesh system.

The only important question when choosing a mesh kit for performance is, “Are you going to wire the backhaul?”
Yes? X55($100/set refurb) or that be5000 for wifi7.
No? Something with more 5ghz channels like the x90 or BE22000.
Go with eero only for parental controls. Way too pricy for what you get.
Decent wifi6 3x mesh should get you 600 mbps throughout the house assuming you don’t have like 5k sqft all on one level.

Wiring is always recommended and will allow you to better very expensive WiFi systems with relatively cheap ones.
5ghz will do most of the heavy lifting for wifi6 and wifi7.
If you use wired, 2x 5ghz streams per mesh is plenty. If you don’t use wires, and only have two streams per unit, you lose half bandwidth every step or worse if other devices are involved. Couple that with your main maybe not being central and having two steps to your office and you’re down to a couple hundred mbps at best.
The more expensive and larger systems have more 5ghz simultaneous streams and can handle wireless backhaul while serving clients or handle double jumps with very little loss but still won’t beat out a mid range system that is wired.
Also x95 appears to be a big upgrade from the x90 in speed stability. Amazon has a 2 pack x95 new on sale for $199. That’s a big upgrade if placed strategically,