The good guys were mostly left-handed. The bad guys were mostly right-handed. It echoes life.
Er, well, specifically, Crono and Frog are sinistrals. Ayla is drawn in concept art typically right-handed, but most of her animations are left-handed. Maybe she's neither. Conversely, Lavos can't possibly be left-handed, since its left-hand appendage (from its point of view), is actually the Lavos Core. Indeed, Lavos is more accurately double right-handed.
=)
I don't care much about the other stuff, but I'll bet you dollars to doughnuts that, even though Ayla is the strongest physical character in the party, she's given typical "female" stats and is both shorter and considerably lighter than Crono. I say, to hell with that!
Oh, and Lucca was born on February 29. It only stands to reason, people!