My experience has been the opposite. I wish Brave was more like Firefox.
I have Brave installed as an alternate browser (originally because sites like Twitch and Netflix performed poorly on Firefox, not so much the case anymore). And there's a noticeable lag when switching tabs that's absent in Firefox. And the memory usage - Brave uses as much memory with 10 tabs open as Firefox does with 100. It seems like "unloaded" tabs are not really unloaded at all, and continue to take up memory (which makes you question what unloading does) as long as the browser remains open.
I'm not sure what you mean by ergonomic, but I've been spoiled by Firefox's openness to customization, it was shocking to find that you can't even customize the toolbar on Brave to have your frequently used features handy.
You can always check the internal task manager to see which tabs/extensions/child-processes are using the most resources. To do so, visit › More Tools › Task Manager in the browser, or press Shift+Esc.
I have Brave installed as an alternate browser (originally because sites like Twitch and Netflix performed poorly on Firefox, not so much the case anymore). And there's a noticeable lag when switching tabs that's absent in Firefox. And the memory usage - Brave uses as much memory with 10 tabs open as Firefox does with 100. It seems like "unloaded" tabs are not really unloaded at all, and continue to take up memory (which makes you question what unloading does) as long as the browser remains open.
I'm not sure what you mean by ergonomic, but I've been spoiled by Firefox's openness to customization, it was shocking to find that you can't even customize the toolbar on Brave to have your frequently used features handy.