Gigabit internet does not require a 10GbE router
BE67 can still provide coverage and capacity benefits, but its largest Ethernet advantage remains unused when the modem, switch, storage, and clients stay at gigabit.
A 2.5Gbps plan can fit either model
BE63's four 2.5GbE ports may be more convenient for several wired devices. BE67 makes more sense when one faster 10GbE path or greater wireless-backhaul capacity has a defined job.
Local traffic can justify the upgrade
Fast NAS transfers, workstation backups, or a 10GbE switch can use capacity even when the internet is slower. Draw that local path before paying for it.
Future-proofing needs a date and device list
List the expected modem, service tier, clients, switch, and storage upgrades. A vague future plan is weaker justification than fixing placement or adding Ethernet today.