The clock uses historical voices taken from telephone network speaking clocks so a rooster call would not blend in nicely with the theme. Interesting idea though. There are some pictures of the latest version prototype here Physical talking clock with no UI and I may well publish the whole lot when it is completely finished. The final version will probably be in the form of a PCB backpack for an LCD 1602 screen if I can squeeze it all in.
I saw that SolarCalculator library when it was first announced and made some comments on it then SolarCalculator library for Arduino . I was impressed by the sleek example of obtaining sunrise/sunset times. If I do another project which needs sunrise/sunset times I'll give it serious consideration.
Those geo-cordinates, incidentally, are not too bad for me. I'm a bit south of Bern.