Welcome to the forum. Start reading the stickys. Also count your blessings... you have awesome parents.
Amen. Let's leave the parenting to the parents, HIS parents. As for your questions, it really depends on what you're looking for. For me, the no HID's is a deal breaker because (and this is going to sound horrible), once you go HID, you just do not want to go back. As for the stripped down radio, tough to imagine a more stripped down one than the current stock one.
At any rate, you need to see if you can live the features or lack thereof and go from there. If the decision is a monetary one, you should also consider resale value as its always easier to sell a car with more options than one without.
And to go against my own recommendation about parenting, PLEASE be careful with this car. It's fairly forgiving but the amount of power really can sneak up on you if you're not paying attention, which is VERY easy to do when you're just starting out.
Anyway, you can spend weeks reading up on the GR on these boards. Do your homework, punny?, and figure out what you want and what you need.