Hardware isn't often the issue, its usually firmware/driver related when the problems occur in my experience. So no matter what hardware you have, running something like OpenWRT et al. can be a massive quality-of-life improvement.
With that said, I've had the best luck with Broadcom chipsets over the years. I'm currently using a Netgear R8000P (which is the BCM4906 chipset), but not on stock firmware.
EDIT: should add an addendum to my initial comment that hardware and software is obviously connected because the radio vendors are writing the driver software in most cases, but my Broadcom recommendation still stands even with that throat clearing.
I do. yes. But the latest stock firmware on that router is surprisingly stable and performant. Not a bad idea to do some burn-in testing with that to see if it meets your needs. If you need to tweak phy layer knobs like tx power etc, you'd have to switch but otherwise there's probably not a need for most folks.
Also, open driver support for broadcom chipsets is very lean, so getting openwrt to work on the wireless side is a bit of an effort. Doable, but definitely not simple out of the box.
Are you sure you don't have an R8000 rather than an R8000P? As far as I can tell, the only alternative firmware for the R8000P is OpenWRT, and the documentation claims only 802.11b/g rates are supported. DD-WRT and Tomato, which would have better driver support, only target the R8000.
At least I had fun connecting to the console UART in order to flash the latest firmware on this R8000P. The one I bought was stuck on an older version with a bug that prevented it from accepting firmware ever again.
With that said, I've had the best luck with Broadcom chipsets over the years. I'm currently using a Netgear R8000P (which is the BCM4906 chipset), but not on stock firmware.
EDIT: should add an addendum to my initial comment that hardware and software is obviously connected because the radio vendors are writing the driver software in most cases, but my Broadcom recommendation still stands even with that throat clearing.