Looks very neat.
Congrats on the purchase, and welcome to the 330i clan:chef:
I would just inspect the DISA valve asap if I were you. If it appears fine, it should be fine.
Also check if your coolant is running between 93 and 96 degrees on the open road through the hidden OBC menu. If not, get the thermostat replaced asap.
If you love the sound of the car as it is, dont fiddle with the exhaust. You will gain next to nothing by removing the 4x cats ito power, contrary to popular belief.
Personal opinion, but I really like the e90's BMW style 194 17" on the exclusive pack e46