I’ve gotten into selfhosting and have 3 mini PC’s

ODROID H4+ for TrueNAS
One for Home Assistant
and another for Immich and Nextcloud

They’re all just plugged into the router my ISP provided with network cables.

I’d like to get a managed switch or a router of my own that can function as a switch and router

I’ll be putting everything in a 10" rack at some point so it has to fit.

Any suggestions or tips would be appreciated, I’ve done some research and looked at options but unsure what is right/wrong

I’m especially stuck on what Hardware to get. Is 2.5ghz managed switch overkill? Should I get PoE for future use?
What brands are good, what should be avoided?