Horn Sub Input Please - Build In Progress!

I am in the process of layout/design of my new theater room. I am going to be using PI 4 Speakers for LCR, and PI 1 Speakers for Surrounds. I designed a set of OD Horn Speakers to compliment the LCR and surround speakers as flanking subs to tame room modes. So the frequency range is 50-200hz

Since this is my 1st attempt at Hornresp and Sketchup, I am looking for input on my design and folding before proceeding further. So there will be 7 total of these flanking subs the front 3 will be under the PI 4's and the 4rears will be under the surrounds in a column configuration. The will be driven with 20 watts RMS.

I will be using a miniDSP 10x10hd, and the plan is to cross the flanking subs, with there respective mains, as well as matrix the LFE channel to theses subs as well for frequencies above 50hz, and then use the Low LFE subs for everything under 50-60hz.


Thanks!!