Mentioned this before but I am still using my 14 year old Buffalo Airstation G54.
Rosa! We've got a wireless-G user on aisle 9! Cleanup!
Covers my entire house, garage and yards, never reboots unless power goes down. My 2 desktops are wired with cat5 to it also. Comcast up to 150 down is only giving me 30 down however.
The Buffalo has been so good and trouble free I really hate to replace it but I did pick up a Netgear R-7000 (AC1900) Nighthawk at a good price a while back. Still in its box. Be interesting to see if anything improves.
Hmm.
I think that you will find your internet performance much-improved with your R7000 router. I know those Buffalo G routers with the Broadcom chipset are reliable, just like the Linksys WRT54G (spiritual twin), but those older chipsets, as you've found out, limit your internet connection (WAN-to-LAN) of around 30-50Mbit/sec. Just a thought, but maybe, time to upgrade? It looks like you already did upgrade, you just think it's a chore to configure a router. (It is. But it should be worth it to you.)
Edit: If you love your Buffalo G router so much, what you
could do, is install the R7000 as your primary wired router, handling the WAN-to-LAN, for your wired devices (your main desktop PC is wired, I hope), and then connect the Buffalo as your wireless AP, for your mobile devices to use. That should give you a wireless environment like what you had before, but alleviate the bottleneck between your ISP connection, and your wired devices (desktop PC).