Well, the Strong Hero's base attack bonus is the best for the same reason that the Tough Hero has the best Hit Dice -- it's what he's good at. d20 has always gone along with the idea that Strength is the modifier for melee attacks. As a martial artist, I find that to be a bit silly, so I've mentally house-ruled Strength to mean coordination and ability to deliver fast, precise, hard movements. This also explains why a 35-pound halfling can have a 16 Strength and drive a short-sword through the average commoner without any trouble.
In d20 Athletics, Baseball players would use Dex to throw the ball and Str to swing the bat.
Therefore, in my mind, the Strong Hero is just fine with the best attack progression.
Most of the progressions made sense to me, at least in the sense of "These are the tradeoffs. If you want to overcome them, here's how you should multiclass." d20, unlike D&D, was designed with the thought that everyone would multiclass. I love the thought of what a Smart, Dedicated, Fast hero could do in combat.
In general, the non-physical heroes got better versions of just about everything -- saves, skills, etc. -- because they're toast in combat. And while we're going for roleplaying and thinking and such, there's still gonna be a ton of combat.
The only thing I don't love at the moment is that, from a brief look, the Dedicated hero looks to have kept some of the cleric's overpowered qualities. It'll be interesting to see if the residual flavor that always made clerics unpopular sticks with him now...
-Tacky