Higher bit-rate video, faster load times, app stability, and edit functionality (which many people repeatedly request, despite it being arguably low-priority because you can just delete and repost), just to name a few. I'm practically a Bluesky fan, and I again disagree with Steve's characterization, but even I see many things that have room for improvement. Granted, Twitter/X should crush them on this alone and they've arguably leveled the field by making their platform worse over time, so heh.
Is it discovery? Algo? Some AI shit?