Hi. My initial thoughts;
This forum might have a few regulars who is using their gear for studio work (which I presume is where you're coming from), but I think you'll get more replies in a forum like Gearspace.com. Pretty messy place, but still a good place for advice on stuff like this, if you can manage to weed out the crap.
The Presonus is in a class of interfaces that are very mediocre. Just as 'consumer audio interfaces' like Focusrite, Audient, Maudio, etc. I think my first priority in your situation would be to get a much better interface. One with two sets of stereo outs, which would let you manage the two speaker sets and their levels from inside the mac.
But why the two sets of speakers and all that money? Put your money and effort into going to showrooms, listening to speakers, and find something you really like. And maybe do some room treatment. Anyway, a crappy interface and speakers with impressive names, is certainly not a good idea, IMO.
I'm sorry. I know that this isn't what you asked. Your graphic of the routing looks OK, but I don't know the exact features of the Mackie w/regards to flexibility.
It would help to know what you're planning to use this for. ITB (in the box) bedroom music production?
Just my two cents.