That's pretty much how I did my theater that's in my signature, but I'm curious as to where your atmos speakers are planned to go since they aren't labeled.
I think I have an idea based on your diagram, but it'd be easier if we knew for sure.
One thing I'd advise is to use an AT screen if you are going all in-wall like I did. I had cabinet speakers in my first theater and I much prefer them over in-walls due to the MUCH better bass output. If you can get speakers with cabinets, but built into the wall, that will get you much better sound. You can build boxes in-wall before you get the speakers installed so that shouldn't be an issue. The AT screen is really great just because all the sound is coming from the screen. It'll help with the theater effect you're going for.
Are you set on the Monoliths just because of what you've already heard or because of budget? I ask because if you're like me and you are looking at the "frequency range" part on the specs page, it looks nice. However, when you look at the graph you can tell they drop off after around 100hz. I don't know what their f3 is, but I think THX says it should be 80hz.
Then you need to consider subs. I have one in each corner of my room and the bass is nice and even. It looks like you plan to do something similar, but I'm not 100% sure without labels. I don't want to assume anything. Do you have an idea on what subs you'll get? If the f3 of your speakers is high, then a good sub/s will help quite a bit at evening things out.
I'm sure others will chime in, but that's my $.02 worth