I've been using Chromium Edge for many months now, and I think that to further diverge it from Chrome by adding customizability to the end-user, a performance menu similar to the Privacy and Tracking Prevention menu in the Settings is cruial.
I've been using many browsers over the years and recently, and I think one thing that Edge has going for it is its memory efficiency compared to Chrome. In order to further give users more leeway in customizability, there should be a menu where people can choose whether the browser will use more or less RAM, since many laptops have limited amounts of it and productivity can be tough when RAM is limited, and applications are fighting for the Pagefile. This could be done by allowing users to enable or disable extensions using high amounts of RAM, and control the browser's PreLoading mechanic, where the browser preloads pages to make commonly used sites load faster by keeping them partially in RAM. This page would detail the impacts of each predefined "mode", and users could also choose to customize one or more of these modes, which advanced users would highly appreciate. Browsers like Opera GX already have similar mechanics, but with less customizability, and like the mentioned oGX, users should be able to easily set RAM limits in the browser, and preset modes would detail the estimated amount of RAM per tab.
This is something that I've been looking for in a browser for a long time and have never found, and extensions aren't able to fully control the browsers processes directly. It would be amazing if the feature was added, and I think it would be highly competitive in the current browser space.