Do something radical ...
and just build an Opera 12 interface, customisation, tab handling, customisable ad blocking and everything that was great and original about Opera, onto a modern rendering engine ... I'd be happy. Stop wussing about with 'new features' and just get the old ones working fast and well.
Opera was my browser of choice from the version 6 (paid for version) onwards (which I think was the first "proper" feature rich release) until they ran out of track, hit the buffers and wiped out the station with the fork-up with version 12.x and 23 with "new features" that didn't include all the basic features that Opera users liked ... von Tetzchner can do it, I still have the faith.