I agree with what prydogga and Fredjo have said, you can tell what's comfortable to you regardless of how long you've been playing and it's better to make a big investment at this stage rather than an intermediate level guitar so look to be spending your maximum budget of $650. You'll get the returns on the money in terms of enjoyment over the next year or so anyway
I know you said you wanted a fixed bridge, so from Ibanez's range you'll belooking for things like the RG321, 421 or similar.
Personally, I'd be lookiing to find a used RG500 (RG550/560 or 570) series or a newer equivalent such as the RG1550 or RG2550 and blocking off the trem.
With regards to pickups, I always think a good bridge pickup on a rock guitar is the most important thing to look at and whilst the standard RG pickups are "ok" look to budget for at least a new bridge pickups from one of the companies that william1993 mentions.
Good luck and let us know what you go for.