#1: A more aggressive cam would be helpful, but it certainly isn't mandatory.
#2: Consult the FAQ. While the big MP62 blower used in the JRSC for the ITR is a nice unit, you will ultimately get more power per dollar with an appropriately sized turbo.
#3: See #2. Granted, nitrous oxide is also an option to FI. But if you're considering a JRSC, I assume you're worrying about smog legality as well.