Looking to Do some more

Hello Friends,
I have recently upgraded from an EdgeRouter Lite to a EdgeRouter Pro 8 in order to get fq_codel properly working on my 150/10 Mbps connection. It's been up and running for ~1 month now and I have notihng but good to say about it so far.
However, I am looking for some additional features that EdgeOS can't yet do for me and I am hoping I can get some assistance.
Basically I am looking for a few additional features: web caching/squid, a DPI-based modern firewall (I really like the one in Untangle), and ad blocking on the network level.
I've used untangle in the past, but it's caching is a $5.00 a month charge, and squid is obviously free.

Do I have any other alternatives that are free and easy to use? Should I spin up a seperate VM and have untangle AND some flavor of linux running squid?
Maybe pFsense just to run Snort and Squid?

Whatever I choose, I will spin it up on a Celeron G1820, 4GB of ram, with an ASRock h97 motherboard I already have, and a couple old Intel server NICs.

I would vote for PFSense, it's GUI features are really nice compared to using all command line on Linux sever operating systems.