I am in a similar predicament since I intend for my BRZ to be my DD until the factory warranty runs out. I am more of a mod noob than most here, and decided to stick with all cosmetic mods. Being without a workspace / car jack space to work on, I've even opted out of any ... 'under the car'... replacements. My current mods: Shift knob, clutch height adjustment, european oem arm rest, and the customized molle seatbelt padding from Endom (all of which are existing threads in this forum if you look hard enough...pm if you need links).
P.S. if you dig hard enough, you'll also find my almost suicide whilst modding my car