If running the tsi first things I normally see are intakes and exhausts. Usually required with certain remaps anyway. Also have seen beneficial results in overall reliability with using a catchcan system in place of the oil separator. Helps delay the buildup of carbon on the valves and does away with the weak diaphragm that commonly fail. So easy to ruin the rear main seal when the pcv diaphragm fails and that causes an oil leak, vacuum leak, and misfires at idle. I don't know what your goals are or bugit but those are where I start with mine or my customers cars.