Late to the party here, but were it me, I would lean towards:
1. Car with the largest knowledge base if you hate inventing the wheel.
2. Car which will compete in the largest field. A fast car is nice, but a fast car with nothing to race against is boring.
crx stuff just popped up. further away, and unfortunately the owner died last year (RIP Ken) but he knew his way around hondas and you'd be helping out his family.
http://www.improvedtouring.com/forums/showthread.php?t=30115
Kinda like my 240SX vs. a Miata. They're about the same power to weight ratio, but they get through corners a touch faster with the same basic setup and can get on the gas sooner on corner exit.. but I run them down and catch them in braking at the end of the straight and they have a hard time getting back around me.
don't let parts support scare you off. it's a prelude, it's been done before, it can be done again. go-fast parts might cost a little bit more but compared to a few seasons of registration fees, tires, and towing even a few thousand in shocks seems paltry.
worry more about what the OEM and aftermarket will suppor tin terms of OEM-spec wear items. like wheel hubs. a dried up supply can bench the car. if the prelude is supported better than the CRX (and I have heard that some parts like that for the CRX are getting rare) then the prelude will be cheaper in the long run.
A friend of mine has an 89 CRX ITA car that is for sale here in NC. Has the OPM inverted shock setup, LS, etc and is in the under $5000 price range. Good starter car. PM me if you have any interest.