Is BPI-R4 suitable for topic title requirements?
What other hardware choices are there for this?
What can the expected throughput be with BPI-R4; others suggested; with running Snort/Suricata on the same hardware? How about OpenVPN; WireGuard performance and which PCIe crypto accelerator hardware may provide an uplift in performance with those applications?
Why don't you ask on dedicated topic?
https://forum.openwrt.org/t/a-new-dual-10g-router-based-on-filogic-880-banana-pi-bpi-r4/
Sorry to shatter your dream, but no wireguard crypto accelerator exists.
Intel IPSec-MB with their AVX512 can actually help on ChaCha-Poly1305 to speed up the encryption
Indeed, same for the latest iteration of QAT.
The R4 may satisfy most of your requirements but I suggest that you personally test and approve in detail the functionalities that you are going to need because you could find a black swan like me (I recognize that it seems that finding black swans is my specialty).