If you know some Python, get Django and start playing with it. Worry about 'scalable' last, and keep 'beautiful' as an ongoing goal that you work on over time.
that sounds a good idea... the JavaScript/CSS and things are biggest pain point.. what to learn first, python or frontend things?
I'd go with Django, just to understand the 'underlying' model of how web applications/sites work. Of course it's possible to do more and more in Javascript too... but you're going to have to run it on a server, and Django's as good as anything out there for 'generic' purposes.