You say "The Calculate node might be a tiny bit slower since it has to parse the mathematical expression". Surely the parsing only needs to happen once, in fact it must happen immediately because only then does it know what input ports to create.
Regarding the 4 file uploads, perhaps there was something else happening at the time, seems I can upload more now.
Regarding more generalised nodes ... perhaps maths is the stand-out example. But I find myself often making sub compositions from multiple nodes in simply for generalisation. For example there is convert text to boolean, int, real, data. Why not one node with 4 outputs. I really doubt there is any measurable performance difference for the sorts of things people are using Vuo for.
Search for "convert point", surely some of those can be compressed into multiple input or output nodes.
I guess this is "style" and "elegance" thing and not everyone will agree, but my vote is certainly for a smaller number of general nodes rather than a large number of specific ones. I also accept there is now a backwards compatibility issue.
Sorry, all fixed. I only just noticed the "Screen with active window" is the default for the screen input on the Fullscreen node. So the fullscreen is being applied to the active window. All works if I just extract the correct screen and feed that to the Fullscreen node, I attach the fixed composition.