91 speaker setup

Fitted my stereo today. Took at look at the speakers in thee front door and in the boot.

Absolutely shocked on the workmanship of how these speakers have latterly just been thrown in.

Like realised after the didn't fit and just let them hang and float there.

I understand that ones in the front have a triangle fitment (Bose)

The rear ones are round but unsure what size. Could be 6.5.

I am interested in what sound setups people have done with both fronts and rears

Ideally I'm thinking components in the front and mid/bass in the boot.

Not a massive fan of sub woofers but I will had one if really lacking bass. But not essential.

So come on guys show us what you have done to give me some ideas

Thanks