I've been learning a lot, fast, by trying to build out the same (very simple) full-stack web application in using different frameworks. Different backends, different frontends and different databases. Admittedly, I've been doing this for slightly more than one week. It's been a lot of fun, I must admit. It's interesting to see the different quality levels in documentation, availability of help on StackOverflow, and tooling.

I'm not approaching it with any real goal other than to see how some other frameworks work but it feels very worthwhile.