I'll likely be migrating over to Proton Pass[1] since I already have a Proton Mail subscription anyway. Seems like it meets all your criteria depending on what you consider to be a reasonable cost for a subscription.
Made the switch from BitWarden to ProtonPass a few months ago. I'm very happy with the switch despite Proton Pass missing some android functionality BitWarden has.
A good friend of mine got suspended for a semester after he found a pretty trivial flaw in his university's password reset form that would ultimately allow him to reset the password of anyone who had an account on the school's network including faculty and administrators. IT discovered him, locked him out of the network before he was able to report it, and threatened to take legal action. From what I've heard, they never fully fixed it. He went to a technology university mind you.
I found a blind SQL injection in my university course management system. Probably could have dropped the entire campus course list... but I didn't try. Found it at ~2-3AM, and so figured I'd bother IT in the morning. Woke up to a locked account and a message from the dean of students to pay him a visit.
I got off with some stupid fine and my online access being locked for 30 days. Was pretty annoying though, because they counted the 30 days only during when school was in semester. I happened to be doing this the final day of the semester... so that 30 days ended up being a lot longer.
Something that came as a surprise to me was the fact that QEMU and FFMpeg are made by the same guy as well.
Kind of depressing; either one of those projects has that person set for life in the job market, and that jerk has both! How am I supposed to compete with that?
EDIT: Just a note, I say this with all the love in the world, and certainly wish no ill-will towards Fabrice. I hope my dumb joke above didn't come off as hostile...I think it's pretty cool that one person was able to build two apps that I use daily.
I've never used Overleaf, but for several years I used ShareLaTeX as my primary LaTeX editor. I've since switched to using LaTeX through emacs but I still regularly use ShareLaTeX's great documentation and if I didn't carrying my Linux laptop around everywhere, I'd probably still be using ShareLaTeX. Hopefully this new partnership won't ruin it.
Overleaf has its advantages (e.g. better git integration) but I haven't heard much praise for their editor. In my own experience, the Overleaf editor is slower and more cumbersome to use than ShareLaTeX. It's much harder to rearrange files and compile time to PDF is much slower. You also can't set your main doc to be in a subdirectory of the project.
I hope this partnership means we'll soon have the ShareLaTeX frontend on top of the Overleaf backend. That would be a truly powerful combination.
[1] https://proton.me/pass