I´m maxing them out right now.
I just got Minh, and now I´m running around at Phin maxing out all kinds of stats; I´m sick of chars missing their targets all the time, or spells that deal poor damage and whatnot.
So, I´m gonna be extreme this time and MAX OUT like a maniac!
Not THAT much, of course; I´m gonna stick to maxing out things that my chars are primarily intended to use most of the time.
Firion is a kind of Paladin, so I´ll max his sword skill, white magic and Soul stat; Maria is a Hunter/Black Wizard, so she´ll master the bow, her black magic and the Intelligence stat.
And so on.

I think this game will be much more entertaining if you get rid of all those battles that take forever (how about an enemy cast of three Slep16? YAWN!!!), and simply überlevel, so that you can defeat all those damn enemies QUICKLY!

It may take forever, but I like this system anyway.
I´m able to reach unimaginable HP and stuff relatively fast.