Hello mate,
I know exactly how you are feeling, I was in your shoes once. Looking around, knowing that I have the money and just get what car I can get but the best thing is:
Seeing as you are young, get a low engine car such as 1.0 or around that and get the driving experience. Insurance will be high, the same for new young drivers. I had my fiesta 1.1 for £1,300 (with parents) which is a lot but we got to start somewhere.
After 2 to 3 years I got a focus then an ST with insurance that I could afford because I'm older, got more driving experience. That is what the insurance companies are looking for. I know that you are excited and wanna add extra touches to your car but that may increase the insurance price.
Best Advice - Sit down, think about the money and the long term investment. Don't splash your money out bec if you do, it will be hard in the future.
Let us know how you get on mate. If you wanna know anything or just a chat PM me or message here.
Cheers mate