W201 project

In terms, the idea is quite simple. I want to give the car a facelift or a new lease of life. When i got the car, many things didnt work properly;

_The engine overheats in town

_Driver's side Electric windows not working

_No history

_No power steering

_Dull audio system.

Audio

so far, this is the audio setup in the car:

The problem is that the system lacks power. The headunit is not very powerful, and only boasts a few features. Apart from tapes, the radio broadcasting is very dull, with NO bass at all!! Rectifying the problem doesn't lie in changing the speakers, as the pioneers are fairly powerful already.Im not a bass freak, but i would like a nicely balanced system that can be fairly loud if required.Hopefully, the lot will be changed. Here's a plan of what i want to do;