I like your approach!
I'm also waiting for my Emira, and use to much time on thinking of audio upgrade.
What kind of DSP will you run?
My plan at the moment is to use Focal speekers as I have used this in previous cars and are happy with the sound.
I plan to use the K2 Power M series in the Emira;
FRAK tweeters on dash
6.5 KM in the doors
2 x 5" Sub KM
I will probably not use any rear speakers, as I think to much speakers tends to fuck up the sound.
I will use Helix M4 DSP to power the front ( one channel to each speaker) and Helix M1 X for the sub's. I've also used DSP from same producer in my MB E class dd, so I'm familiar with the software and pleased with the sound.
Have you idea if there is any signal cable into factory Amp that can be used for the DSP or do you plan on using the high level signals?