A modern programming language that makes developers happier.

kotlinlang

Well, a large node tree means a large slot table that each recomposition has to traverse. But as long as you have skippable groups that's probably not a huge deal. A tree of thousands of nodes shouldn't be a problem, but then it becomes what those nodes do. If they're traditional UI do you need to do measure, layout, and draw passes? Those could be expensive and you need all kinds of optimizations for that to be as lazy as possible. Ultimately what you do and it's performance is going to depend on a lot of factors and I wouldn't waste too much time trying to anticipate where the bottleneck is and just go for your idea.