Lets take a step back,
Just to cover my bases you purchased a brand new car and you dont have "the funds". Im not going to make more assumptions than I can back up, but Im guessing your a bit young to be driving a high performance car in the first place. These cars are not "cheap", they take more maintenence than most other cars in their price point and becuase they are AWD they also carry higher price tags when something goes wrong like a sidewall puncture on a tire ( gotta swap all 4 or pay to have tread removed on the new tire because diffs ).
That said if you have the money to buy the car and you can afford the payments I would spend your first 2000 miles driving the car with a pen and paper in your door pocket. Every time you stop take notes about what you like and what you want to change and add a line about why it needs changing. If you do that for the net 2000 miles then you can decide if you really need new exhaust tips because you like the look of color shifting titanium or if you really need a new shift knob because the stock one is super light.
I tell most people the same thing. The number one part that needs work is the nut between the steering wheel and the seat. Invest a few bucks in HPDE courses and learn to handle your new car, they are amazing machines but they need to be treated with respec otherwise youll just add to the growing list of kids who smashed their new subaru.
Finally just to parlay any notions a new exhaust will NOT make any additional power. Your butt dyno will be happy becaue "louder must mean faster right"? but you will not make any more power by swapping out your OE exhaust with an aftermarket unit unless you also change the J pipe, midpipe and mufflers with performance models AND pay to have the car tuned either by a professional or you invest in a tuner like the Cobb accessport and tune it yourself. HP numbers on muffler boxes are a joke, especially on advanced ECU controlled vehicles.
Im sorry if it comes off as harsh I just dont like to see people making bad calls. If you have any questions in particular about parts please dont hesitate to shoot me a PM, Im glad to be of assistance wherever I can.
Slow is Smooth > Smooth is Fast