I have a 2015 Pro and even if Safari uses less battery, I feel the same thing about Firefox. It is fast and smooth and has less bugs than Safari. However the thing that made my laptop feel cool again is the overwhelming amount of extensions available. There are so many of them and they really improved the ux. Safari has way less and most of them are commercial projects by big techs that collect datas or paid extensions by indie devs that I still can’t 100% trust because they’re closed source. Most of the extensions you find with the search bar on firefox is open source.