How are these classes not better than some of the base classes? The bonus feats (pg 77) can be any feat they meet the prereqs for. Or instead, they get to choose from a list of actual class features.
To me, Spellcaster > Sorcerer, and Warrior is a little better than Fighter. Expert is unclear, but probably isn't too good.
Spellcaster > Sorcerer because they get a bonus feat a 1, 5, 10, 15, and 20.
The bonus feat at 1 can be a Familiar. The other feats are bonus feats [or class features] the sorcerer never gets. You can use them for actual metamagic. Maybe Evasion?
The skills are already better than the Sorcerer since you can pick UMD and Diplo. [4 free choices]
The spells are better than Sorcerer since you may pick divine ones too.
The same number of spells known too.
The only downside is 1 less spell slot per level in the early game. However this single less spell slot is granted back at later levels.
No sorcerer only spells since you can 'only' pick from Sorc/Wiz, Cleric, or Druid lists.
Warrior >? Fighter
The bonus feat at every level is any you qualify for, not just fighter bonus feats. And you can get actual class features like Evasion, Uncanny Dodge, and Sneak Attack.
You don't get to have heavy armor proficiency or tower shield proficiency, which can be somewhat bad.
For sure, I'd pick Spellcaster over Sorcerer...