No, we are all not rebooting our 2.3.4 nodes weekly.
Can you get to the webgui and look around when it acts up before you reboot it?
Look at the usual things. disk space, ram, mbufs, etc.
If you can get a status output: https://firewall_ip_address/status.php download that file before rebooting next time so you have one while it's failed.