I was thinking when I first installed it, 'huh, something isn't quite Boost with this". I had to turn off Material design to get the old bluish theme back. Not sure if this is what you mean but maybe it can help!
It's preferences for looks and behaviour. You could always back up current state, import the ones from BfR and if you don't like it, restore the backup.
Awesome! Just did it. And then saw the give Boost some love by buying rocket fuel and decided to throw in another couple of bucks :) Love the app. I am using Lemmy for the first time today because of it