Howdy and welcome.
I'd upgrade the TC next. I heard it makes 4EAT owners very happy. What year is your WRX? If it is an 02-05 I wouldn't bother too much with the TMIC until I was gonna get a protune or a new turbo, as it wont give any more power from just bolting it on.
If you have an 06 I'd recommend a new IC just for cooling purposes if you live in a hot climate 100+ deg.