I think it depends how you prioritize speed, convenience, security, privacy, features, etc. Also depends on the OS's you need supported.
For me...
#1 Brave - Hits a nice balance of speed, security, and has unique in the Basic Attention Tokens system.
https://www.theverge.com/2019/3/4/18249623/brave-browser-choice-chrome-vivaldi-replacement-chromium
#2 Firefox - It's open source, packed with features, more secure than most, and I its presence makes the internet a better place imo. We have all seen what a browser can turn into with little/no competition(see: internet explorer). This is the browser I actually use the most but it's not the first I go to and I'm just hoping more people will give Brave a chance.
https://itsfoss.com/why-firefox/
#3 Chrome - While I'm trying to ween myself off of the ecosystems for google/apple/microsoft, sometimes it's just fast and easy to use a few of the google services I'm still on with Chrome. I'm sure Google will screw this up eventually(like they did with music, and photos, and voice, and hangouts, etc) so hopefully I'll be completely past Chrome when the day eventually comes.
If someone were a researcher or the type of person to have a dozen or more tabs open at a time I would also suggest they give Vivaldi a try.
If someone was most concerned about security and privacy I'd probably suggest they give TOR and/or Epic a chance, but be prepared to twiddle with a lot of settings and remember at the end of the day the only thing that can truly keep you secure is the monkey punching the keyboard.