Juse use easyoptouts. Way cheaper for same thing.

You already have a pihole. I assume you like it. You could buy a cheap minipc/NUC and set up proxmox on it and learn to set up and configure a second pihole as a virtual machine. Then you’ll have a server running with the ability to expand as needed. You could look into setting up new network gear (like tp-link’s omada) and run the software controller in a VM. Or you could dabble with HomeAssistant and get into smarthome. Or set up a photo management tool like Immich. Like others have said, find a problem you want to solve and use these tools!