Before the remap-
I would recommend before going up there buy a Forge 007p DV, the VW standard one is prone to crack and hinder performance by giving a boost leak. Also a Pipercross Panel Filter. That should see you good results.
Just be warned this extra power and torque can put strain on your clutch and if its going this will almost certainly finish it off. Good upgrade for this is a VR6 and G60 set up
read hereAfter the remap-
Full turbo back exhaust, Milltek are the most known, but you can get a custom job made up for a bit less. Decat or sports cat if you have a few bob to spend.
Front mount Intercooler(FMIC) to cool the air down.
The list can go on just depends on what you want to achieve.