Greetings, I'm new to the Forum.

[swizzle]

I guess there is an upper limit to the reasonable playlist length. Who'd a thunk? ?

It really depends on the client, a few thousand items on modern hardware shouldn’t be a problem, but thirty thousand will make most browsers cry. I’m sure we can optimize it some more but I think it’d probably be better to make it easier to create smaller subsets of your library via smart playlists / filtering rather than try to accommodate huge lists.