I know it's been a long time since I've posted, but with all the buzz surrounding the recent Cleric preview from the upcoming Essentials line I figured I might as well throw in my opinion. The similarity to previous editions, where new class features are gained through leveling, is readily apparent. This is actually one thing I didn't like about 3.x edition (the edition that I started playing; I can't comment on anything earlier), so I'm a little nervous about that. I always felt like certain class features were a big part of the appeal of a given class, and I kind of felt gypped when I didn't start out with them. The Druid's Wild Shape is the perfect example, as a Druid didn't gain that ability until 5th level. Our campaigns generally started at 1st or 3rd level, and were almost always one-shots. A failure of the group, I know, but I was still stuck with playing a Druid that didn't quite feel right (I liked shapeshifting). I know my group couldn't have been the only one that didn't get past low levels very often. After all, everyone likes to get experience with different classes.
The fact that the Druid gets Wild Shape right out of the box, and the Wizard can always cast spells (thanks to the at-will system), etc., were some of the biggest reasons why I was drawn to 4e. So a step backwards to level-dependent class features seems like exactly that-a step backwards. But then again, 4e classes obviously gained different abilities when they leveled; it's just that they were called powers. The main difference being that no one power comprised a huge chunk of a given class's essence, and there were often multiple "versions" of an ability at different levels. Scorching Burst may not be called Fireball, but for all intents and purposes it serves the same thematic purpose. Your Wizard could blast multiple enemies with arcane flame. Perhaps the Essentials class features will feel more like powers (or rituals), in which case I wouldn't mind such a progression.
Another major difference is that different classes will have varying levels of complexity. This is a welcome change, as new players would benefit from simpler classes, but also veteran players who control multiple PCs, for example, but don't want something quite as streamlined as a DMG2 companion character. Besides, the point that's been made about Daily powers on Martial characters not making sense is valid. I can live with it because it makes Fighters, etc much more interesting, but there's an appeal to having the more "realistic" version as well.
This brings me to my final point, on why I think that the Essentials line is overall a very good thing for the system. It adds variety, and has the potential to appeal to more people. This is especially nice in the case of those classes that have original versions and Essentials versions (Fighter, Rogue, Wizard, Cleric, Druid, Paladin, Ranger, and Warlock, for now). Say, for example, you really like the Wizard archetype. Now you have 2 different ways to play a Wizard within the same system. This goes beyond having a choice of builds. What the Essentials classes do is give you a different mechanical interpretation of a class. Personally, I'm very interested in how they re-imagine these classes. These new takes on classic classes may appeal more to some people than the original 4th edition version. And the beauty of it is that they don't render the original versions obsolete, because there are invariably going to be people who prefer those versions to the new ones. Personally, I expect that I'd rather play the original Fighter, even if I do recognize that a simplified non-Daily version enhances the game. And given the cross compatibility, and the fact that Essentials versions are free to pick up any class power, including the original ones, it seems like players can even create a class that's a happy medium between the original version and the Essentials version.
As always, more options are good.