Thanks for the all of the overwhelmingly positive responses.
There are two areas I'd like to address:
First, balance is something that is never finished. The game has never been balanced and that includes even now. People always have, and continue to, find PK power combos. This wouldn't remove that problem, but it would lessen it. Yes, this would take a bit of effort in the design phase to balance. However, it is much less than what would be needed to code in a new class or race. Also, please remember that after this change is put into play, future balancing becomes much, much, much easier than it is now, for reasons I outlined in the original post.
Second, about how this would work for spells and attacks.
Basic attack is base attack as it is now.
Advanced attack is second attack.
Expert attack is third attack.
Master attack is fourth attack.
As classes earn second attack (communers), third (melees/hybrids/rogues), and fourth (warriors), they get the corresponding level for free. Warriors spend no points to become masters. Also remember that there is a limit. A rogue or hybrid can not learn fourth attack, even if they wanted to. Communers would be capped at third attack and so forth.
This applies to all the mini-paths. A berserker cannot learned advanced staff. A berserker cannot learn expert dodge (rogue hybrids) or master dodge (only dedicated rogues). A warrior/berserker cannot learn advanced meditation (DKs, BLMs, monks) or master meditation (paladins, communers, casters). This is a balancer and ensure that berserkers will still play like berserkers in the end. It is good that we don't know exactly what each character's perks/tactics are, but we should have a general idea of how the class will operate and think. This maintains that.
As for spell/racial skill details, the general idea is that stronger spells get weaker benefits/ease of play/passive benefits. Here are some examples I drew up:
[B]basic burning hands[/B]
--advanced burning hands (can blind with smoke)
--master burning hands (ignores saves and resistances)
[B]basic flame arrow[/B]
--advanced flame arrow (the spell hits the target group, similar to sharpmetal)
--master flame arrow (shoots a free flame arrow whenever the caster is targeted by a fired weapon, even to other rooms)
[B]basic fireball[/B]
--advanced fireball (adds 10 to the target's saves when calculating damage)
--master fireball (ignores resistances)
[B]basic firestorm[/B]
--advanced firestorm (explodes twice on the tick, giving two damage rolls and chances to blind)
--master firestorm (synergy damage bonus to all fire spells 5% when active, similar to fireshield now)
[B]basic fireshield[/B]
--advanced fireshield (cancels the weakness to fire)
--master fireshield (a further synergy damage bonus to fire spells of 5%)
[B]basic protective shield[/B]
--advanced protective shield (-30 AC)
--master protective shield (cannot be dispelled/dropped by dispel magic/haymaker/chii bolts)
[B]basic curse[/B]
--advanced curse (lowers the the target's defense/damage rolls by 5%)
--master curse (massive penalty to luck)
[B]basic shield[/B]
--advanced shield (-40 AC)
--master shield (missile shield)
[B]basic catalepsy[/B]
--advanced catalepsy (no poison/plague damage in catalepsy)
--master catalepsy (enables HP regen in catalepsy)
[B]basic blood vow[/B]
--advanced blood vow (can cancel the vow after half of the duration has expired--similar to monk's empower)
--master blood vow (can have two separate blood vows at the same time)
[B]basic sleep[/B]
--advanced sleep (target can't regen during the sleep)
--master sleep (sleeps the target group)
[B]basic curse weapon[/B]
--advanced curse weapon (no damage to the weapon when cursed)
--master curse weapon (no nodrop)
[B]basic mana charge[/B]
--advanced mana charge (halves the flare damage)
--master mana charge (can fully charge any type of weapon)
[B]basic malform weapon[/B]
--advanced malform weapon (weapon starts with nodrop/burnproof)
--master malform weapon (each kill counts as two kills)
[B]basic shed[/B]
--advanced shed (double skin HP)
--master shed (follows the slith, similar to a mirror image)