The Wizard gets schools, the Sorcerer gets bloodlines, and the Warlock gets pacts.
No, that is not what is happening. Each individual sub-class is getting a completely different spellcasting system.
If my "system" you mean "fluff to describe how it is done, whether it needs certain components, what it looks like in the world, etc.." then yeah, but I don't see that as a big deal. But if you mean each one gets a different quantity and spell/psy level at each experience level, I disagree. I think they will be sharing the same chart for quantities, and what level of spell/psy they get at those experience levels.
The Mage class shares the hit points, attack, Esoteric Knowledge, Scribe Scrolls, Brew Potions, and the feat progression.
Yes, though I strongly suspect the final version will switch "scribe scroll, brew potion" to simply be "class ability" with a sub-class list of which ability they can get at that level. I know Mearls said they will get scribe scroll/brew potion in his off-the-cuff tweeted answer, but then he grants it might be wonky for some sub-classes (like sorcerer), and I am thinking that leads to simply a broader designation of "class ability" or "class sub-feat" or something on that line in the chart, and then each sub-class will list which ability/sub-feat it can get. So for example (off the top of my head) mage and warlock gets brew potion, while at that same level psion gets detect creature, warlock gets improved pact ability, etc..
The subclasses under that (Wizard, Warlock, Sorcerer, Artificer, Psion) each provide a whole different spellcasting system with access to different spells.
Yes. Though again, not sure what you mean by "system", other than mostly a fluff role playing explanation of how it is done and what it looks like, rather than a mechanical difference.
Nevertheless, this is how it's been done in almost all forms of D&D, each sub-class gets it's own spell access list.
The subclasses under the Wizard, Warlock, etc, will provide the same thing other subclasses under other classes provide, a list of unique abilities.
I see what you're saying, so illusionist, a sub-class of wizard, will have their own unique abilities and spell lists. I think that's right. They will tweak a minor number of abilities, and alter the spell access list. So instead of, say, brew potion, the illusionist might have silent spell. And instead of magic missile on their first level spell list, they might have minor image.
Which is pretty much how most editions of D&D did it, and I never found it cumbersome and difficult to work with. You have four base progression charts, then each of those has some major tweaks to how the base class does things, then specialties of those sub-classes have relatively minor tweaks to how the sub-class does things. It does streamline things pretty nicely, I find. Organizationally, it seems to make sense. And progression-wise, for hit points, quantity/level of spells/psys, ability score/feat bumps, levels of class abilities, armor access, that sort of thing, it makes sense as well.
Hey, at least (so far) this edition doesn't have four categories of saving throw charts to look up
