Sorry Sam, but I think what you describe it is easily doable in plansets.
I have multiple title blocks, in my case since we use 11 x 17 as much as possible they have all the standard notes in different locations and even at 90°. I just choose the relevant title block for each drawing in the set, depending on the shape of the plan. Some give a wide aspect some a tall one. From what you are describing above, plan sets would work as easily as the multi's, with no need to copy/paste the title blocks, as the project information is in the project not the block. The only real difference would be the notes that you move round - as that would really confuse the title block - but they could be inserted into each drawing as a symbol or even a standard drawing that contains nothing but the relevant notes.
So in essence, you would draw your relevant plan insert standard notes (either a symbol or a standard drawing), move around to suit and then add to the relevant page in the planset. Slightly different, but in my opinion as easy as the multi-drawings.
The template could even be set to add the relevant plans to the relevant pages automatically. Although I keep meaning to do that with mine, and haven't got round to it yet. I do believe it's possible though.
However, if your system works for you, and it isn't broken, then there's little reason to fix it!
Not trying to change your mind, just making an observation!