By my maths, it's 20 without those three but I'm including Dylan Wells and Luca Ross in that.
To have a squad of 20 and still feel short in so many positions (full back, midfield, up front) is a concern. Too many defenders that probably won't be first picks (Balmer, Koutroumbis, one of O'Donnell or McGinn), and too many players in other areas that we almost don't count as options because they have contributed so little for various reasons (Nicholson, Stuperavic are the obvious ones).
Basically my thoughts are that while 20 isn't a huge squad, it feels unbalanced and it still to me feels that there are too many players who may not contribute a lot over the season...