What would you want from a forge?

(This is more or less open ended, but sorta directed to users of Jujutsu and other version control systems. However, if you have a workflow with pure Git that isn't covered by many major forges, I'd appreciate hearing them too!) I'm referring to features related to version control and the presentation/behavior of repositories itself, rather than things like SPA/JS vs server-rendered HTML, etc. There have been many ideas in this space, such as Tangled, GitHub's stacked PRs, forgefed, etc., but I haven't found a place where people really voice their opinions and discuss on the design itself. While stacked PRs/MRs, alternative collaboration models, etc., are definitely on-topic, I've found almost no discussion on, e.g., the presentation of tags/commits/tree/blobs themselves, which seem to be largely uniform across forges other than minor formatting differences.