more fuel, more boost, cooler air (meaning more air) - but where do you need the power? lower revs? might be worth considering a VNT.
generally bigger intercooler allows you to cool air quick and more effectively, allowing you to run a bigger turbo without major issue, but of course then you need more fuel for you extra air
personally minor modifications would be better rather than going for any sort of major power increase - recently a friend has done all of these mods to his 300, found it to be too pokey, a little bit smokey at lower revs, and worse on fuel, so hes backed off the fueling and the boost a little bit, he estimates he is running 135-140hp now, while also getting a whole chunk more torque. worth mentioning you're also increasing the forces going through the transmission too.