Does the base kit include spacebars, and if so what lengths are they? It's hard to tell if they are convex (i.e. spacebar shaped) or concave, and there are no U sizes.
Mostly never. If you are using Colemak, you can flip row 2 and row 3, the K works fine for row 4. The only problem is "N". Which you can replace with novelty
I believe how it works is for the majority of the double-shot MT3 sets is that back when they were creating MT3 they created a single mold that includes all the keys. This is why almost every double-shot MT3 set has the same sets with the same keys. If they do have extra custom keys the whole set will cost more because of the extra molds that had to be made. But why did they include command and not option? Good question! The longer they make MT3, the more molds they will create so we can only hope some changes are made eventually. Personally I think ortho should include another 2u spacebar, and why not just have command and option be in a 'Mac' kit and include 1u versions of each.