The Brave window has a Titlte bar. It’s good if you use windows or Linux kDE but in ElementaryOS it’s wasting of space - Especially if you are using a laptop.
My suggestion is to create an option to hide the title bar and the menu. Let the command bar and the tabs. It will look as Brave fullscreen option but without been fullscreen.
To understand what I’m talking about you should look at the Epiphany Browser for ElementaryOS. I believe it will fit pretty good for Unity, Linux Deepin, ElementaryOS, etc.