I use the BE800 directly as a router. I will then set up a Mesh WIFI network with Dedo BE65. But to be honest, they first have to come down significantly in price. I don't yet have the expertise to recommend anything else.

Unfortunately, I cannot answer this question yet, as I have not yet installed and studied this BE800 router.

Use the RE19000 as a satellite extender with your BE800. Works very well.