The new Human Versatility HEAVILY favors Melee and Skill based builds. In fact, most of the human attributes favor physical combatants over casters.
However, the degree to which Human Versatility does it is just astounding.
Human Versatility provides FIVE DIFFERENT types of bonuses, and not ONE specifically benefits Casters.
The New Human Versatility provides bonuses to Weapon Accuracy, Weapon Damage, Saves, Skills, And AC.
A fighter will be able to potentially make use of four out of five of those. A Rogue could arguably make good use of ALL of them. A Caster? The Saves boost? Maybe.
Yes, I'm certain bards and clerics could get some milage out of the skills/ac perhaps... but Wizards and Sorcs are left completely in the cold.
Instead of providing a boost to weapon accuracy, allow Casters to increase the DC of their spells for the set duration of the time. Or, allow there to be a Spell percentage Discount during the casting time (i.e. 10%, 15%, 20%, 25%).