I've been on lemmy mostly since it's a bit more mature particularly in mobile usage, however I think kbin overall has more potential once it matures a bit more since it has more interesting functionality (Microblogs, Magazine CSS, etc.). This functionality could lead to some interesting UI/UX paradigms, which IMO would be a bit of a breath of fresh air in the mobile space over the good amount of "apollo-inspired" lemmy apps. The apollo approach is good for lemmy apps, but I see kbin as being something more diverse and as such would necessitate a different approach. Though I think the most important thing long-term for kbin is for it to improve its federation, without that it becomes a jack-of-all-trades master-of-none platform.