"The iPad visualization area size options are remnants of a time when iPads only came in one size. As such there is no any template for iPad pro."
Our report creators are not familiar with web standards, and would like the built in layout suggestion tool to work across all iPads
Good to know, and with that in mind, I can actually cast the old resolution aside (the current iPad config seems to be tied to the 1024x768 variant).
The options for visualization area size actually comes from the preferences stored at the server. While we could and should add more device sizes out of the box in Spotfire, for your Admin it is possible to add any sizes you may need. See attached screen shot from the admin manager help.