I agree with the other guy. Your best bet BY FAR!! Is to just go ahead and stay on site at either the Royal Pacific (My choice) the Portifino (Awesome but more expensive) and the Hard Rock Hotel (only one I've never stayed at.)
Your room key is your express pass, gets you to the front of the line as many times as you want. Allows you to ride over and over again letting you at the front of the line everytime.
For me this part of it, together with just the fact that the onsite Hotels at U are awesome, makes this the only way to go for me. Yes you may spend a few more bucks, but you are going to blow a fortune no matter how you look at it, so whats a couple of extra on top of everything if it makes the experience 10 times better, and staying onsite at Universal does make the experience 10 times better.
The view from the RP of the Islands of Adventure is spectacular, I always request a top floor IOA view and it is one of the best parts of my trip everytime. Plus its walking distance to the parks, and Jimmy Buffets is the first thing you come to at the end of the RP path, then IOA. You can also take the boat into the parks of course, but the path is a good option.