Guide to filtering web content (http and https) mitm squid squidguard
I now recommend that you use both, WPAC as the default and transparent with splice all as backup. So software that has no proxy settings still get redirected to the proxy in stead of getting blocked by the firewall rule 80 443. For android you can manually set the proxy, sometimes splice all can show SSL errors when web browsing. I will clean up the guide when I have time.