I’ve just set up a hAP-mini (RB931-2nD) with ROS 7.10, using the default config and QuickSet, for a customer to connect to my dual-stack PPPoE server running VyOS (using FreeRADIUS for AAA) - each PPPoE username gets one global static IPv4 /32 (with the usual NAT to RFC1918 addresses behind the router), global static framed IPv6 /64 for the PPPoE link itself, and global static IPv6 /56 delegated for use by the customer on their networks behind the router (no need for NAT for IPv6). IPv4 works out of the box, but IPv6 configuration is incomplete - good to see the IPv6 firewall (only outgoing connections allowed, incoming blocked by default), but the PPPoE link only gets link-local addresses and no working IPv6 behind the router, the default config needs a few more lines added for IPv6 to really work (as in 10/10 on test-ipv6.com).
This is for dual-stack PPPoE single session for both IPv4 and IPv6 (as offered by me, I’m running a small local ISP here), the necessary changes might be different for dual-stack DHCP, depending on the ISP. Still it would be nice for MT to provide that as part of the default config (possibly disabled if some ISP needs it but it breaks things with some other ISP). Other things I made from the default config (this depends on the ISP) is to set PPPoE MTU and MRU both to 1500 (RFC4638 support), enable WPA2-PSK AES (really should be the default even if password is just the router serial number), and set only 20MHz channel width (40MHz rarely gives much better performance in the crowded 2.4GHz band). On the other hand, I don’t see why QuickSet includes options such as Nstreme/NV2, this is for advanced users like WISPs and not for typical home use.