As an update, I went to Mickey's and several things came up.

I initially wanted to put the amp/s under the front seats but it turns out that my car has vents underneath the seats so there isn't much space. The shop recommended amps from the Punch PBR series. If I were to get "regular-sized", amps, I would have to do quite a bit of trunk work which I really want to avoid.

Based on my music preference (rock), the shop recommended Focal's Expert series (either Flax or Polyglass if I remember correctly). Cheaper options would be JL's C2 series. Equivalent DLS speakers are okay too but I was informed that the sound signature is quite laid back. I was told that an outboard processor (Bit Ten) is optional but based on what I have read on my head unit and the benefits of an outboard processor, it seems to be something that I should go for already so at the very least, I square away the source signal section of the setup. We also confirmed that my rear doors have separates and while I don't necessarily have to change the speakers, the guy I spoke to recommended it so that my front and rear are matched in terms of sound signature (or just turn of the rears and avoid the expense altogether). Regarding the subwoofer, he suggested an under-seat system from Focal prior to seeing the car but with the vents underneath, that's a no-go so I'll have to go with the conventional sub box in the trunk route (or forego the sub altogether).

I did some quick math and it looks like the entire system will reach P100k so I'm going to have to think long and hard about this.