I see. If the issue is specifically with wifi performance from the home hub, then I'd suggest using one or more dedicated wireless access points.
I have extremely good experience with the Unifi
access points: I have two of the AC Lite ceiling mounted, and they give great coverage around the home. They are dual band, with a raw 867Mbps bit rate on 5GHz; I can easily achieve 400M+ in real throughput after setting wide (VHT80) channels. The more expensive AC Pro or AC HD will give faster rates, if they're also supported by your laptop hardware.
The other good thing about the Unifi kit is the management software: it lets you see all your APs, which clients are associated to which AP and at what signal strength, how much data consumed by each client, schedule firmware updates etc. Also supports multi-SSID, VLANs, RADIUS authentication...
But it sounds like you're already using the R8000 just for its wifi, in which case it should continue just fine with the new home hub (or you can try it actings as a router without the home hub). Ethernet-wired PCs will benefit the most from the gigabit speeds, of course.