Many thanks for the ref on controlling to the order of macros in a palette. That is just great.
Using a persistent variable to identify the next-to-be-run app should also pretty much solve the problem associated to the second idea. I can program a macro based on a hot key that retrieves the current activated app (say Fantastical), consult the sequential list to find out the next one to be run, and activate it.
I’ll try do come up with a working macro!
Thank you!