I'm 100% comfortable with BAT, because the (at least so declared) goal is ethical ad-blocking. And if you don't like it, you still don't have to use it. You can disable it completely and I appreciate them leaving you the choice.
I won't buy into it with actual money, but I do use it to donate to sites. Although I rarely use Brave tbh. I only have it in case some stupid website doesn't run properly on Firefox.
It's tempting tho. Brave is a way better and more versatile browser than Firefox is out of the box. I won't recommend Firefox to normies seeking better privacy for this simple reason. If I tell them to just install a bunch of addons, configure everything right and get used to a new UI, most will question whether they really want to switch right away.
Chromium is FOSS and Brave has already made strong claims about not merging anything Google pushes (e.g. in the recent extensions controversy). I have very little concerns regarding that.