100% concur with the suggestion - particularly for a 'power user' - to completely separate routing functions from a wireless AP. Dedicated solutions for each will result in best-in-class performance, 'jack-of-all-trades' combining wireless and routing functions will result in very poor performance in nearly all areas.
You can get a VERY effective, line-rate-QoS solution with something as basic as a 1GB CM4 module combined with this:
and a very inexpensive switch. If you're less of a do-it-yourselfer, there's this that's also fully supported:
and also quite powerful for the job.
I'm not as familiar with Google WiFi, but were I you, I'd either see if I could get a third to act in an AP mesh and put one on each floor with the 'main' one physically located near a mini-router as above (to provide maximum coverage and maximum function) or, depending on where your cable modem can be placed, put it, the dedicated router, and a switch in the basement (where you're probably not seeing a lot of wireless use) and use the two APs you've already got in a mesh without having to buy another Google unit.
There's a lot of ways to skin the cat, but all of them (that are worth a damn) involve cleanly separating wireless radiation from basic route/firewall functions.