I wouldn’t call Vivaldi ‘a good alternative’.
brave at least has cared about maintaining their source code on github. Vivaldi, on the other hand, just [vomits tar.xz on their website]https://vivaldi.com/source/) and that’s it. they also have made ui closed source.
they don’t have an opt-out for their data collection.

I personally use nothing expect librewolf(hardened Firefox fork). but brave is a sane choice for those who are spoiled by chrome.
the only praise I hear about Vivaldi is their tabs(?).