I always wanted a comparison to ropes. Every time I see ropes mentioned I always think "why not use RRB trees?". It seems like less housekeeping, but with all the benefits.
If you like radix trees, you may also find this article interesting and useful: https://vincent.bernat.ch/en/blog/2017-ipv4-route-lookup-lin...
What tool were those tree structure Illustrations created with? They look really nice!
I would love to add a good RRB implementation to the persistent benchmarks at [1] to get a state-of-the-art comparison between RRB and BST in a persistent context. Duration, of course, but also number of bytes copied etc.
https://rtheunissen.github.io/bst