I apologize that I do not have a logical solution. In AutoCad you could do a page setup for each layout tab. In doing so you could specify that a sheet was 8x11, 11x17, 24x36, 30x42x 36x48 and so on. Then when you would publish or print it would automatically print the pdf or plot the correct size.
Revit seriously needs similar process. Where I work we use multiple sheets size. All the above listed are in 99% of our projects. Currently have multiple print setups save for each paper size and each size as color or black and white. However this means that we have to publish multiple times.
Ultimately the goal is that you could click publish hand select every sheet you have created in your project. Run and then each pdf would be correct size.
