It's really hard to not have a unique fingerprint in a casual browsing experience. Even with minimising techniques because some of that will make you stand out and so the easiest way is to look like the crowd. You only need a few pieces of low entropy information to make you stand out. Spoofing is detectable and so can be discarded when generating the fingerprint.
Tor browser plus ubo is going to be your least fingerprintable route.
After that I'd say Firefox with arkenfox's user.js plus ubo.
You can get Fennec + arkenfox on Android which is Mull Browser.
Arkenfox uses the RFP feature you enabled plus some other things like letterboxing so your monitor resolution doesn't give you away.
If you're not using tor you need VPN or your IP is going to give you away.
I suggest reading the arkenfox wiki for more info.