Great. I'm going to comment only on the things that I would do differently - if I don't comment on something, that means I like it. :)
And solving all the OG 13th ed. problems after each chapter.
Don't do them all. Do enough to feel like you're making progress and learning something, but save some for review later. Try a medium (middle-numbered) one first, then go up or down depending on how easy or hard the first one was for you. But save a decent number of Qs for later.
One *major* issue is that the real test will *never* tell you, hey, I'm about to give you a divisibility problem! You will have to figure out what each problem is for yourself and you will have to jump back and forth randomly among topics. Most of your practice needs to be in that form.
In fact, I wouldn't do more than 2-3 OGs at the end of one chapter before moving to another chapter in the same book. After doing a few of the chapters, I'd then start mixing from all the ones I've already done, so that I can start to get mixed practice even before I'm done with all of the books. When I move onto the 2nd quant book, I'd toss in one or two randomly from the 1st book, just to keep me on my toes. And so on.
So you may still mostly do all the OG Qs by the time you're done with the strategy guides for the first time, but they won't all be done chapter-by-chapter only. They'll be mixed and more spread out over time.
MGMAT CAT exams on the 1st/2nd, 6th and 7th week.
6th and 7th is too close together. Early on, at least 3 weeks between tests - make substantial progress before bothering to spend 3.5 hours taking another one. The only time I'd do a CAT only one week after another CAT is towards the very end.
Other than that, in general, your approach looks good. Let me know how it goes!