The difference is that the Wizard is not restricted in practice to only the three basic, pure elements of magic that the Sorceress is:
The Zann Esu, or Sorceresses as they are generally known, are on a quest for the "perfect" magic in its purest form. They feel that the other disciplines of magic are haphazard, and have instead chosen to focus strictly upon elemental magic.
The Wizard uses these, in conjunction with nature magic, originally reserved to the Druids, and time magic, which is mostly new (with a few scant exceptions from Diablo II). The Sorceress is also of the Zann Esu in the deep jungles, whereas the Wizard is from Xiansai, way, way north and across the ocean.
The basic principle that they can both function as "glass cannons" is in common, of course, but you need that in basically any game like this (multiplayer ARPG) where you choose characters based on their individual play styles and skills/abilites. The glass cannon is well-loved by many players, including me, and I would never want to see it go. As such, it's essentially a staple of RPG's that one is able to be made. So, naturally, the Wizard is a glass cannon, like the Sorceress, like the Sorcerer in Diablo I. The difference, however, is that because of the new rune system, she can function in different ways than just a glass cannon.
So, I completely believe she is a new character, albeit one that *can* function under the same old gameplay, but has other ways of use.
The Barbarian, on the other hand, is the exact same Barbarian from Diablo II, in both lore and msot of his skills, and in the way he functions.
The Wizard uses these, in conjunction with nature magic, originally reserved to the Druids, and time magic, which is mostly new (with a few scant exceptions from Diablo II). The Sorceress is also of the Zann Esu in the deep jungles, whereas the Wizard is from Xiansai, way, way north and across the ocean.
The basic principle that they can both function as "glass cannons" is in common, of course, but you need that in basically any game like this (multiplayer ARPG) where you choose characters based on their individual play styles and skills/abilites. The glass cannon is well-loved by many players, including me, and I would never want to see it go. As such, it's essentially a staple of RPG's that one is able to be made. So, naturally, the Wizard is a glass cannon, like the Sorceress, like the Sorcerer in Diablo I. The difference, however, is that because of the new rune system, she can function in different ways than just a glass cannon.
So, I completely believe she is a new character, albeit one that *can* function under the same old gameplay, but has other ways of use.
The Barbarian, on the other hand, is the exact same Barbarian from Diablo II, in both lore and msot of his skills, and in the way he functions.
My opinion.