@freak
Hello!
Good, the infamous bottlenecks caused by the OpenVPN TAP driver should be resolved. However it's strange that CHACHA20 provides you with higher performance than AES does.
A possible explanation is that your system does not support AES-NI. Your CPU does, though, so you should beat CHACHA20 performance with AES-GCM, if you can enable AES-NI.
Wireguard must be faster than OpenVPN with CHACHA20, because Wireguard runs in the kernel space and CHACHA20-POLY1305 implementation should be fine,. Running in the kernel space, however, has security implications that must be considered. OpenVPN with AES, in an AES-NI supporting system, linked against latest OpenSSL which includes assembly code (at least for Linux), is faster than Wireguard according to our tests, even though OpenVPN runs in the userspace.
Wireguard offer is planned, but as you know it's a wreck lacking many basic features: no DNS push, no dynamic IP address assignment, no AES or other ciphers support, no TCP support, fixed bijection of real IP addresses onto client keys/VPN address, clients real IP address storage in a file, thus posing paramount privacy as well as technical issues.
Many people will be disappointed and worried when they understand the implications of all of the above. Many other people will not be able to use Wireguard at all (mobile ISPs blocking or shaping UDP, countries blocking or shaping UDP etc.).
We will release software aimed at patching, when possible, those numerous problems, but we need to keep approaching and offering Wireguard with care.
Kind regards