New build and an Alpine INE-S920HD

H2O_Doc

If you don't read the MAZOC section, a brief update - I just went from a 2012 7AT to a 2014 6MT and I have some rebuilding to do (some old parts retained, some things changed). Comments and as advice welcomed:

I've said elsewhere, I'm not a fan of nav HUs, BUT I picked-up an Alpine S920HD for $299. I figure a non-nav double din with the functions I want will be as much or more, so, I grabbed it. Good unit? Should I keep it?

I am keeping my dual 12" Kickers powered by 1000w RMS.

I am keeping my Pioneer 4 channel that puts out 100w RMS x 4 @ 4 ohms (150w @ 2 ohms).

Because of a dealership good, they are installing a rear view backup camera and I won't need to worry about that.

I have a set of Mirus Hybrid Audio 6.5s. Considering using them incurs no cost, should. I go with those? Note that they are coaxial. Strong opinions one way or the other?

As I did with my last system, I will likely put something in the rear speaker spaces (I did Polks last time). Any suggestions here?

Thanks much as most of you know lots more than I on this matter. I appreciate you taking the time to comment.