Hello,
I'm afraid that we are not really there yet. You are right that a lot of puzzle pieces are already in place and Genode can certainly be used to build interesting application scenarios. Within Genode Labs, we are regularly building quite sophisticated scenarios including VirtualBox, Arora, Seoul, Rump-kernel-based file systems, and many more components.
But for being fit as a general-purpose OS, there is still the need to address some remaining points, in particular proper packaging. Right now, we use run scripts to build whole system scenarios. For comprehensive scenarios, the build can take hours. This is acceptable for special-purpose systems but it does not scale enough for a general-purpose OS. The work flow of building and using the latter should be far more interactive. E.g., installing new subsystem on the fly without the need to rebuild a system image or even reboot the machine.
That said, we definitely strive for Genode to become a general-purpose OS. So we will take on these challenges. This intention is best illustrated by our recently added GUI stack (the composition of window manager, nitpicker, decorator, window layouter). So stay tuned! ;-)
Of course, you are very welcome to investigate Genode as a general-purpose OS on your own. E.g., porting the Debian bootstrapping to a Noux instance would certainly be an interesting project. Or another (and in my personal opinion more thrilling) idea, port the Nix package manager to a Noux environment.
Cheers Norman