Using footnotes for blocking is an interesting idea I haven’t seen before. It has the advantage of being very neat and legible. I’m not sure I understand your plan for writing in Qs though. Most SMs I’ve seen write Qs in the margins, typed or handwritten, but your margins look fairly narrow for this. Maybe you can post an example. I’ve never felt the need to color code my call book, but I know some SMs find it useful; maybe you can see if you really need the colors before you do the extra work.
I do sometimes include blocking in my call script. I hole punch my calling pages on the right side of the page, and put it on the left side of my book, and have a corresponding blocking page that is hole punched on the left side, and put that on the right side of my book. Notes on my blocking page are numbered, and I’ll either hand write those numbers on my call book where the action happens, or type the number in at the appropriate spot (bold and grey highlight). I am not a memorizer, so I find it useful to have all the info together during tech, to remind actors where they’re going if they forget in the midst of other changes, or if designers are asking me about a character’s blocking, and so I can update blocking information as it changes. When I’m running understudy rehearsals, I can explain what’s happening technically at the same time I give blocking notes. Plus I just don’t have to have two binders, or one really, really fat one.
If your whole script is already typed up with blocking the way your example is, you might as well keep blocking in as you have it, and just shrink your text to keep the pagination when you add Qs, if that’s important. Or just go with separate scripts so you don’t invest too much energy tweaking it. In the end there are lots of ways to set up your books, and this is a great chance for you to learn what does (or doesn’t) work for you. Since it sounds like this is your first show, I'd suggest finding a method that is the least labor intensive; you're going to have a lot to deal, and don't want to be spending too much time creating the perfect formatting.