Also consider outside your home too - either permantly VPNing back through your home network, or (ie for Android) Tracker Control, which will block most ad / sdk / geo trackers that it knows about.
The Pi-Hole itself is very straightforward if you're cool with using docker - the example docker-compose.yaml on Docker Hub just worked for me. But getting your devices to use the Pi-Hole instead of their usual DNS server can be harder than it should be.
Nah mate, if you set your PiHole to be the DHCP of your network, it will force DNS server settings onto the devices it's handing out IPs to. Just set the PiHole as DHCP server in your router and it'll be fine.
I had to put my pihole on a brake for a while. I had it installed on a raspberry pi 3 and it destroyed 2 SD cards in a month. Now it just runs piVPN and all is well.
Gonna reinstall next time I get a newer raspberry.
Check out the overlay filesystem. I'm using it for one pi and have had the same SD card for years. I don't know if it'll work for pinole, but may get you thinking in a new direction.
I just learned that san disk has a 10 year warranty. Today I made a claim for a 5 year old sdcard. Maybe worth a shot. (Just check with ypur manufacturer.)