I would do the VTEC head thing if I were doing it. Provided I had the money to do it right.
I think you'll see the most gains that way. My memory isn't so great this early (5:30 herer) so I forget the HP numbers on that engine, but when I think about what 195 HP would be like in a CRX it definetely makes me wake up a little.
Building an ITR engine might require a lot more work than one might think though.