Flint 2 as an AP for Flint 3—or vice-versa? Or something else as AP?

I recently installed a Flint 3 to replace a failing old Netgear Orbi setup. Unsurprisingly, the Flint 3 isn't reaching all corners as well as the mesh setup. I want to add a wired access point (AP). Since I bought and installed the Flint 3, I've learned that some prefer the Flint 2.

Would the Flint 2 work well as a wired AP? Or maybe it would be better to swap them (Flint 3 as the AP to a Flint 2) because the Flint 2 has stronger radios? Or maybe I should just be buying something else entirely as an AP? Curious what you all are using when you need to extend the wifi's reach.