Bassik, I have said this along with kaanage to you before. What you are after is not acheivable, especially on the assumed budget you have (less than $25,000).
You are after the handling and body-roll characteristics of your old Honda Integra Type R. It's not going to happen. As I have pointed out to you before, you are talking about a car that was built in the Honda factory, shipped elswhere, completely pulled apart again and re-built with ompletely different suspension geometry, components and even setup which included the re-location and addition of different mounting points. It also had chassis strengthening rails welded into the monocoque. The entire car went from spot welded together to 75% (from memory) seam welding.
You literally are talking about a race car that was tarted up for the street.
A front anti-roll bar upgrade WILL help with body roll. As will stiffer, progressive rate springs with matched dampers. To get the handling you are after though? Never going to happen due to the suspension setups you are comparing. Double wishbones and multi links vs torsion beam and MacPherson Struts. Yes, you can make a very good handling car, but if you want the Type R handling experience, sell your polo and buy another Type R. Or buy a 2nd hand Boxter / Cayman which is even better. Probably still has more body roll though.