I think I understand why they are doing it. They want an easily modular way to allow swapping of spellcasting systems while maintaining the flavor of the (sub)class. So if you wanted a Wizard Illusionist with spellpoints in your campaign, you would take the Wizard subclass and bring over the Psion's point system.
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I agree on basically all your points.
If the purpose is swapping spellcasting mechanics without changing flavor (and viceversa), this option could be indipendent from classes. It could be presented as a general module in the PHB or DMG. All that's needed, is make sure the spell progression by level is designed so that together with the flexibility of the spellcasting method and of the spell list, the "spell point" variant is balanced with the "at-will" variant is balanced with the "encounter-based variant" is balanced with the vancian variant. This is nevertheless needed also in the current case. But if it's a rules module, then the benefit is much larger because it can also be applied to Clerics & Druids, and maybe even half-casters, while proceeding in the current way means this will apply only to arcane casters.
Making warlocks and psions subclasses of mage means that they're probably going to use the mage spell list and be differentiated by only a few class features. As someone who loved the 3.5 warlock, with its unique approach to spellcasting, at-will spells, and unique list of invocations, this is simply not acceptable to me. I don't want to play warlock that's a mage who just happened to get his spells from a pact. That's not what a warlock is to me. And Psions have never, ever been mages.
But let's say that they do make psions and warlocks totally distinct from other mages, with their own invocation/power lists, unique class features, etc. But if they did that, why not just make them their own classes in the first place?
Exactly!
Spell lists are going to be different in any case, they've already tweeted about it. In any case, different or not, it is exactly the same whether they are classes or subclasses.
For example, I would like to explore the possibility of Warlock being able to cast healing spells. After all, since they are granted spells by powerful entitities that are less than gods but more than mortals, they are in a sort of intermediate position between divine casters and arcane casters. It might be however restricted to some warlock subclass, a "white witch" or something like that. But as a general concept, I think it would be more interesting if the Warlock had at least a spell list very different from wizards, or not use spells at all.
I understand the idea. But I don't like it. The classes may have underlying similarities, and certain classes may be able to exist as variants of each other. But I feel that on the whole, Sorcerers are distinct from Wizards. Warlocks are not Psions, and Artificers shouldn't even be magic users at all!
Yes indeed. I am not familiar with how the Artificer was done in 4e, but I would expect such a character to work very differently from a spellcaster.
Also note that currently the Mage class is almost an empty shell. Spells come from the choice of Wizardry, special abilities come from the choice of Tradition, and then there's feats. What is left is only Scribe Scroll, Brew Potions and Spell Mastery, all of which will probably be removed because they just cannot work for
all possible alternative to wizards... SS and BP may work for Warlocks, be a stretch for Sorcerers but are just inappropriate to Psions. SM works only for those who don't already cast at-will.
Therefore, what is the purpose of an "empty" class? The only true effects are (1) creating a multiclassing restriction (which you can bet it will be later handwaved after enough people will complain for years) that would not be there if using different core classes, and (2) fixing hit points, proficiencies, attack bonus, which may be inappropriate for some of the subclasses so these will be once again modified by such subclasses... All these are simply
pointless complications that wouldn't be there if using separate core classes.
Now if the whole purpose is instead just to create a "class group", why don't they just do that? Say that Wizards, Sorcerers, Warlocks and Psions all belong to an (empty) "Mage superclass", and Clerics, Druids and Monks belong to an (empty) "Priest superclass", and Barbs, Fighters, Paladins and Rangers belong to an (empty) "Warrior superclass" etc.
But then let all those arcane casters have their own class so that the
design will be unconstrained.
Just look at what they have done for Clerics and Druids! IMHO they did a GREAT job, but it would be impossible now to merge these without major changes. By keeping them separate, they are free to design Wildshape in a way that works well on its own, and Domain Spells and Channeling to work well, without being constrained that the different mechanics must coexist in the same class.
It also just looks better on paper, that a player looks at the Wizard class and perceives it as being "just as big" (i.e. important) as the others, rather than looking at a Mage that takes 5 times more pages (not counting spells) than everybody else.
