I understand - the issue is the randomisation of the Evenly segments. There's not currently a way with A2S to synchronise random numbers along columns. The only solution I've found to work so far is something like the one above, which I find is still quite flexible. Nonetheless, I'll talk to our development team and see if it's something we can improve because this isn't the first time I've been asked this question lately.
Regarding the mismatched heights. It's a rounding error so sometimes an extra floor gets added. You can avoid it by enabling Slice for the segments.
Best,
Paul