Well, the idea is good, i'd play a game like that. Damn, i played the heck out of Battlefront 2 exactly because i loved those big space fights with fighters and stuff blowing up and lazors everywhere!
But.
It's a big project. And by big, i mean enormous.
Even scaling it down a bit, it's still a too big jump from your previous experiences, you need to take it slowly, step by step.
Some time ago I had an idea for a game, a "simple" RTS that would be used in my final exams in University. Since then I took a lot of steps back because i realized that i had neither the know-how (on this i'd like to say thanks to Alex, looking at how things like ships, skills and weapons are handled code-wise gave me a lot of food for thought lately
) nor the time for such a task. So i took out 3d graphics, real time and a lot of other thingies. Now at least i have a chance at making something out of my ideas in the next 2 years. Maybe.
I know you're excited for your project and you want to make something that will be remembered forever, but for each step forward you have to take your time and think. Thinking is the most important thing to do when you're developing: you may be a code-bender for what i know, but if you don't start thinking a LOT before everything you do you won't go anywhere. And while this is less true for small projects (i don't have to think for ten hours before coding a simple calculator) it is the most important thing for something like this
So, my simple advice is: take all the time you need. Learn, experiment, start from scratch for ten times, but whatever you do: never rush ahead of your possibilities.