re: First boat: Cal 2-27, Pearson 28 or Islander 28?
Some thoughts from an actual Cal owner with an outboard. I have a Cal T/2 which is the IOR version of the Cal2 27. The outboard saves you 200+ pounds and prop drag, but does require a reinforced stern mount (mine came that way from the factory).
A 9.9 longshaft will push you to hull speed at low RPM's and stays in the water in all but the biggest waves.
The Cal is a good solid boat - mine has been bulletproof for 38 years. It's also a big cheat with an outboard because it's rating is based on the inboard version - it won't take long for your local club to catch on should you do the outboard conversion.