I mean, that's your prerogative, but why settle for ads at all? Especially from a browsers that blocks ads from advertisers who don't pay them?
I've had numerous performance and memory issues with Firefox but from my testing over the years it's the closest to Chrome/Chromium you can get.
Also Firefox gets new features fairly regularly. It's still an "innovative" browser, as opposed to Chromium which is mostly stagnant. Vertical tabs are pretty cool.
Personally, I just got to like Firefox over time.
It is more true to my ideals.