Personally I use corporate-like naming scheme for my devices, the format is:

[AABB-CCCC-DDEE]

AA: Location of the device - HQ (home), CL (cloud).
BB: Role of the device - HV (hypervisor), SV (server), NW (network) and workstation (WS).
CCCC: Device brand (for NW), application running (for SV), and workstation purpose (for WS).
DD: For server and workstation - OS running on the device (WN=Windows, LX=Linux, MA=macOS). For network device - their role on network (RT=router, AP=access point, SW=switch).
EE: # of the device, year of purchase for WS.

For example, here's my router, KASM server and my gaming PC hostnames:

HQNW-UBNT-RT01
HQSV-KASM-LX01
HQWS-GAME-WN16

Still trying to optimize this naming scheme, like removing all the dash, but currently too lazy to do it lol.

Pihole is a good start, though I personally use my Pi 3B+ for printer server over WiFi since I have a dumb Epson printer.