Is there a way to have different rows to have different widths to plan module arrangements across different cases in one convenient location?

Say four rows 3U 88HP with an Intellijel 7U 104HP case.

no, that is not possible

Ideally, with those 4ms pods, could a mismatch in depth be highlighted?
-- liquid_air

In the Data Sheets view of your rack you see the deepest modules like in a spreadsheet view.

Beep, Bopp, Bleep: info@modulargrid.net