I always say, start from ground up. No matter what you mod, you will feel it more if your car can put it on the floor. Tires first.
Shoes and watches make a man. Rims make a car. Aside from looking good, lighter wheels will help acceleration. 1 Lb off your wheels is equivalent to 20 Lbs off your car. For a low powered car, weight reduction will really help power to weight ratio.
You want to go fast? But think about stopping fast first. Braking can shave off more time than fast car with small brakes. Even off the track, you will benefit in situations on the road. Go, turn or stop is all about control and the more control you have, the safer you can drive.
You can grip the road great and go fast in a straight line but unless you love drag racing and Nascar (redneck racing), you would need suspensions to keep center of gravity low and centered for good balance. Adjusting the alignment will keep your contact patch optimal in turns and help steering response.
When all the footwork is done, then think about power and it all has to do with breathing, unless you want to mess with internals like cams, pistons, etc, which is expensive. Get more air in with intakes (cold air for power in high end and short ram for power in low end and better response). Throttle body and intake manifold to eliminate bottle neck. Then exhaust - less resistance to air flow for better fuel economy and more power.
All interior mods are for your driving comfort.
Hope this is a good overview for you on modding.