EdgeRouter devices come to mind, latest EdgeOS update from UBNT was about a year ago (so it’s either already perfect or no longer maintained - I suspect the latter…), the hardware is still fairly decent, and VyOS looks like a natural upgrade path. I’ve been using ERPro-8 for BGP with full tables a few years ago, and still have two such boxes lying around.
I know that porting to all those various ARM architectures would require a lot of resources, but I wish to support this feature, especially for Ubiquiti EdgeMAX routers whose EdgeOS is de-facto EOL. Those devices with Cavium Octeon CPU are very nice and performant.
VyOS would be a natural replacement due to their common Vyatta origin.