If everything you need works fine, just carry on as usual.
The main difference is that Flatpak packages run in isolation from the rest of the system, which can sometimes get in the way of getting things done. For example, you won't be able to drag & drop files from your file system to upload them (unless you use the Downloads folder which is explicitly whitelisted by default).
As for updates, typically they'll come much more often on Flatpaks than they do on Debian packages. Although, in the particular case of Brave this is not true since Brave keeps their own repository to distribute the Debian version of their browser, which you can install.
You can see a more lengthy discussion here: