Well, we can pivot this thread into speculating on future subclasses, because it's pretty clear this will be where 5e will be expanding. My understanding is that there are a few from the Alpha that were cut.
Nope. The subclass list from the February leaked Alpha is identical to the final subclass list. None added, none removed.
Also, so far there's been nearly no difference between the Alpha and the final previews. So far I've noticed all the changes we've seen so far are:
-Bard gets 2 more known spells and doesn't get a cantrip at level 16. Also, the final version doesn't mention Font of Inspiration going up at level 10 and 15.
-Sorcerer doesn't get a cantrip at level 16
-Cleric's Destroy Undead feature is slightly behind(starting at 1/2 instead of 1) and they don't get a cantrip at level 16
-Wizard doesn't get a cantrip at level 16
-Scribe Scroll is no longer a feat
-Martial Adept feat added
-Healing spells are all halved in effectiveness and add your stat mod
-Swift spells are gone, replaced with Bonus Action spells(which do the exact same thing)
-A couple of minor renaming of abilities without changing their effect
Otherwise every preview has shown that the leaked Alpha is 100% accurate