Vivaldi, mostly because of the “quick commands” keyboard navigation. Opens an Alfred / Spotlight style input, type what you want and jump right to that feature or toggle or website or whatever. Love me some good keyboard based nav. Definitely one to check out for anyone used to working a lot with Sublime.
I’ve been using OnlyOffice and, as an M365 subscriber, would definitely recommend. The UI is also very similar to MS Office which can help new Linux users.
Anecdotally I’ve also found it snappier than Libre. But then I’m not a heavy office suite user so I’m sure others mileage may vary but it’s a perfect fit for my needs.