CrossRoads:
Not to mention the backwards usage of Eagle where you had to choose the part you are using when drawing the schematic
What? How do you create a schematic if don't start with a part?
Maybe my explanation was worded a little funny (English is my second language). What I mean is that what I remember of Eagle, you had to choose what footprint you want to use when drawing the schematic. In KiCad for example you just use the schematic symbols you want and after you have drawn a schematic, you can then associate each schematic part with a footprint of your choice. That way you can draw a schematic even without knowing what kind of footprints your parts will eventually have, for example I could use the same schematic for through hole mounted parts or SMD parts.
But this is getting off topic, which was Arduino boards as KiCad modules (aka footprints), so that they could be used when designing shields etc.