So I think the answer to question is - absolutely nothing. The very few missteps Brave has made get broadcast from the ends of the world. The fact the biggest thing people can find to complain about it is some crypto stuff, which is opt-in and easily completely disabled, or an autocomplete tagging a referrer - that was patched out in less than 24 hours, is strongly indicative of the quality and integrity of the browser.
That functionality (which would modify some literal URLs typed in by users, not just make autocomplete suggestions!) was present in the source repository for roughly a month and a half until it was disabled by default, and remained present as an option for over a year after that.
https://github.com/brave/brave-core/commits/master/component...
You may mean that it was modified less than 24 hours after users noticed it and raised an outcry, but that still doesn't exactly inspire confidence.
Can you imagine google chrome bringing Tor integration into their browser? Why not?
Further, there is no way to pre-emptively disable the cryptocoin elements on new profiles on the same Brave installation.
Chrome feels a lot faster than Firefox to me (Especially on Facebook!), yet I still use Firefox to resist Google's stranglehold on the web.
Hope you trust Mozilla with that same level of info (in twenty years)!
Misleading way to say more APIs, I presume?