For races, I'd add the Half-Ogre, as a common archetype that's not represented. I'd probably use the regular Orc instead of Half-Orc. These two races might need some tinkering to balance them out a bit (the Half-Ogre might look more like the Half-Giant, but without the psionic stuff).
I'd have more nonmagical classes. The Paladin would choose spell-like abilities instead of becoming a spellcaster, and the Ranger would get nonmagical abilities. They could become spellcasters through PrCs.
The generic Wizard should be the master of metamagic. The Wizard would gain more metamagic/item creation bonus feats at mid and higher levels. This would give them something to give up if they take PrCs. The Sorcerer would choose one of the Bloodlines from Unearthed Arcana (a minor one), and could upgrade via short PrCs.
I'd rewrite the Monk. It would be a generic and much more customizable martial artist. I'd probably ditch the name, too, which has too much European cultural meaning attached to it. For now, let's call it the Mystic (from the basic D&D set). Basically, the Mystic would have a Combat Style (like the ones presented in Unearthed Arcana) and instead of hardwired special abilities, it would choose "Chi abilities" like the Monk's special abilities and the Tattooed Monk's tattoos.
I suppose this is more like 4E than incorporating d20 stuff into the PHB, but variant classes and options are probably the most appealing d20 stuff out there for me. (I love Unearthed Arcana.)