There are a few known issues here and one of those is the duplicate devices shown in the selector. The discovery code has been completely re-written in Mosaic 1.1.1 (coming soon) so you should see some improvement there.
Having said that it is common to see discovery issues with ISP-supplied routers. We typically recommend replacing the ISP router with something more robust or placing a more robust router between your network and the ISP’s router. The choice depends on the ISP and how dependent your connection quality is on the use of their hardware.
As for recommendations, I hesitate to make these as they do very by market. In the UK we’ve had good luck with the Netgear Nighthawk.