So...looks like I am shopping for a new router.
Any objections to the NETGEAR R6700 Nighthawk AC1750 ?
I would recommend going for a price point you are willing to re-spend every 2 years. The Netgear R6700 is currently going for $85 on Amazon and if getting two years for that price is fine with you then go for it.
An access point is typically the most exposed device on any home network as it is the only one with an Internet/WAN port. Also, in the next two years, I expect we will see better adoption of WPA3 security (including on Roku) and possibly see 802.11ax become cheaper (but possibly not included on Roku for a while).
The TP-Link AC1200 is selling around $40 and should fit as a replacement for the DIR-655 capabilities.