sudo is complex with a lot of code and options.

doas is small, simple & secure from OpenBSD.

If all you want is root priv without remembering two passwords on your box, doas is fine. If you want a complex system of admins and users with fine grained permission control sudo may be a better option.

I use ' su -' much of the time and just use a root shell.

Actively replacing sudo with doas on an OS that includes sudo in the base system seems pointless imo.