Mechanically, the characters were entirely different (sorry [MENTION=37579]Jester David[/MENTION]). They entirely went away from the AEDU framework where each character was designed the same with the same number of powers. They had an entirely different mechanical feel, and that lead to some play differences as well.
Now, they were numbers-compatible with the earlier characters - it was the same edition so they could co-exist with other characters and run the same adventures. I seem to remember that some may have dealt better or worse if you changed up the number of encounters per day a lot, but that was a lesser quibble.
The classes were streamlined.
No, they were not, they were actually less consistent in design and put in a redundant 'padded' format.
Some say that they were more like earlier editions to try to woo the players who were still playing 3.5 or switched to PF, and in some ways they were because they didn't follow AEDU.
And don't forget returning players from the fad years. OSR was taking off at the time. Thus the "Red Box" cover re-printing the fad-era one.
There's nothing about the AEDU system that necessitates each character to have the same number of each type of power at the same levels, that's just how 4e classes happened to be designed up until the PHB 3
Even in PHB 3, the resource numbers remained about on par, even if psionics used encounter power points to augment at-wills instead of getting separate encounter powers, it was a comparable '
Encounter' resource.
And that was the key difference. AEDU could have been ADU or AED or per Round/Minute/Day/Week or Attack/Defense/Social/Exploration. The important difference from prior eds wasn't adding 5 min short-rest recharges and formally breaking out 'Utilities.' It was giving all player characters rough parity in resources, regardless of desired character concept. About the same number of at-will, encounter, milestone, and daily resources (including surges as well as powers). About. There were variations: Defenders & primal classes got more hps/surges, controllers fewer. Wizards got extra at-will cantrips. Divine classes got an additional encounter in channel divinity, leaders in a surge-trigger of varying sorts. Etc. In spite of (and with the help of) those variations, a player could play the character he wanted, without having to accept the innate inferiority of a lower-Tier class. Wanting to play an innately-magical concept didn't force you in under the glass cieling of Tier 2 as a Sorcerer. Wanting to play a valiant warrior without any magical abilities didn't drop you into Tier 5. Or, to compare to the classic game, wanting to play a bookish mage didn't mean you'd have to be suicidally fragile and wait, throwing darts most rounds, until 3rd-5th level to become a regularly-contributing member of the party.
Essentials may have been a mistake, but it definitely wasn't back peddling from the original design goals of 4e.
Sure seemed like it. Where 4e delivered much better class balance (though still, certainly not perfect, and still favoring 'caster' types) than any other edition of D&D had before - or shows any sign of shooting for in the future - Essentials clearly back-peddled from that, gutting it's version of the martial classes and relentlessly powering up and expanding the wizard at every opportunity. Oh, and re-introducing broken magic items, and mass errata to 'bring X back into line with the classic game,' pretty indicative of very intentional backsliding.
Sure, it did other stuff that wasn't exactly backsliding - power inflation and feat bloat aren't exactly backsliding, for instance.
I actually purchased the essential books because I was told they would be good for casual games... maybe they were compared to core 4e (or even 3.x/PF), but since I have 5e now I can't picture myself using them for that...
Essentials, as a system, was not as good for casual gamers as 4e was, but the smaller-format RC was convenient to carry around, FWLTW.
The logic at the time was hard to follow. Some new players were confused by the numbering of PHs, thinking that maybe buying a PH2 would be as good as getting a PH1, or thinking they needed all three. So, to address that, instead of having a new offering with just one PH, they split the PH in half, put it in two books, neither of which sounded like a PH, and made the material redundant, then labeled buying said redundant material 'Essential.'
While I agree that pre-essentials 4e and post-essentials 4e are both great and best kept separate, I wouldn't necessarily label Essentials as the "basic" version of the more "hardcore" 4e. It was marketed that way, but that was one of the many mistakes that were made with Essentials.
Another of the odditites leading up to Essentials was the 'need' for a 'simple fighter,' even though the fighter remained the most popular class, regardless of what was done to it in each ed. At least, post-E, the game delivered on a 'simple caster,' the Elemental Sorcerer, as well.
I've heard a theory that Essentials was designed, intentionally, to fail. I wish it sounded more far-fetched.
