Being able to load extensions at run-time could be a pretty big advantage. Have "apps" you can install on the micro-controller. >but in practice you hardly can

Being able to load extensions at run-time could be a pretty big advantage. Have "apps" you can install on the micro-controller. >but in practice you hardly can exploit your microcontroller's power using such a non-compiled high-level language With micropython you can mark a function to be compiled, or even write a function as inline-assembly. Like normal python develop quickly and optimize the expensive parts. Micropython makes it quite easy to optimize the expensive parts with the viper code emitter and inline-assembly options.