Is there any benefit to reboot the vps account once a day during low traffic hours?
A couple of sysadmin buddies like to see servers restarted once in awhile, but once per day would be a bit much, methinks. The main thing that I have seen happen is in larger networks of interconnected computers that depend upon services across the network; a NFS file server goes down, and perhaps the automounter gets into an unusual state that can't be cleared by service restarts. But on a largely self-sufficient server, there's so much less of that sort of thing; you should be able to measure reliable uptime in months, not days or weeks.
My home server has been up and running for over 300 days, no sign of memory leaks or performance issues. That's how it ought to be!
And frankly, KnownHost is more likely to need to reboot the physical server to upgrade a kernel more often than that, so you'll get your VPS restart that way in any case.