Yes.

Instead of a preshared key shared by all sessions, each session gets a different key.

With WPA personal, if you compromise the key, you can record traffic and decrypt forward and backward in time. With enterprise, you can only decrypt a session. The fundamental technology/encryption is the same.

I don't know. My guess is that since the weaknesses are in the protocol, adding a Radius server makes management easier but doesn't change the mathematics. This means that the network is more secure from things like weak passwords, but not handshake attacks.

I see from Wikipedia there is a new WPA3 protocol, and that's where I would start if I was worried about security to that degree. I am not, so I have not upgraded openwrt on my router.