Big subject! I have a Later Swiss list that is on the way. And I am always on the look out for help. I think that CoE might only cover the earlier Italian Wars, before gunpowder gets too dominant.
Late Swiss will be welcome. I think the Italian Wars are about the end of the period for WAB/COE and their progeny. Still doable since firearms are not yet predominant (unless the Swiss let their heads get to them and they insist on chargind engtrenched spanish arquebusiers...).