I can strongly recommend privoxy too. It can block everything that Pi-Hole can, and more too, but in a easier to use way. For instance, privoxy has a simple online tool to show whether or not a URL is blocked, and you can temporarily enable/disable blocks if you need to. As it doesn't use DNS to block traffic, there's also no problems with out-of-date blocks cached in the DNS.

It also offers finer grained blocking since it works on the hostname of a site (and also the URL path for unencrypted traffic) Privoxy is also lightweight enough to run well on a RPi.