With the way the Birdy folds, removable pedals aren't needed on the Birdy.
My experience with the Big Apple is excellent, As you when seeing the puncture protection rating of the Big Apple, I was a little afraid about puncture, but in practice its much better than the Marathon Racer, I didn't had any flat with the Big Apple even with riding on trails with them. There are Marathon in the Birdy wheel size, I never tried them they are narrower than the Big Apple.
Actually, due to several experiences, I do not fully trust the rating of Schwalbe, I had for instance (in another wheel size), the previous Marathon Almotion OneStar rated 6 for puncture protection and riding the same places as with the Big Apple, I had two flats in a short time.
Te reason why a moved to a 50t chainring is that I also felt the highest slightly too high and it actually become higher with the Big Apple that are wider and higher than the Racer giving a bigger overall wheel diameter.