It's good that they are going to experiment with non-Vancian* wizard subclasses, but IMO they will still end up with non-Vancian arcane classes instead.
*although the Wizard class itself is not really Vancian anymore
I hope backgrounds become more like actual backgrounds. Knight was never really a proper background. A squire would be a more appropriate background name. That way if you are a knight, you might have the squire background, or maybe even just a blacksmith or a noble.
I disagree with this. Backgrounds perfectly represented "your role in the world", aka as your JOB i.e. how to make your living.
A Commoner or Artisan works, a Thief steals, a Bounty Hunter collects rewards, a Jester gets tips, an Aristocrat just has some revenue from property and so on... I wrote somewhere that a glaring miss was a Merchant background, but other new backgrounds could be Servant (your master provides for you) and Monk/Friar (your monastery provides for you).
The idea is that backgrounds aren't just what you were before you became a Fighter or Wizard, but also what you still are when you come back from the dungeon: this was in fact the reason why your background gave you skills
which you still improved at by level... because you didn't stop being a Bounty Hunter or an Artisan (even tho the exact activities didn't need to be told at the game table).
However, the WotC designers themselves are confused by their own ideas, or seem to forget about them. "Knight" was a perfectly valid background because e.g. a Knight makes his living from property (you are assigned lands when granted knighthood). Of course this is not the only possible Knight, there is also the Knight-errand archetype, but the background was a good start.
I'm not against Knight turn into a Fighter's subclass, after all Fighter was going to be the most common class using this background, but this change does lose support for some interesting characters.
When I say that designers get confused, I have in mind that they probably just thought "but
adventurers make more money from treasure after all!". This actually means
we don't really need backgrounds in the game after all. This is absolutely true, in fact we didn't have them in past editions... But the point is that backgrounds aren't there because we NEED them, they are there because we LIKE them, and those who don't like them they don't have to use them. This is not yet the case because skills are linked to backgrounds, but it will be the case starting from next packet.
However, they seem to be wanting 3e-style multiclassing, and I don't see how those work together. Do you have to pick a MC-friendly subclass before you know you're going to MC (like 2e MC kits)? Do you get a subclass for each MC? That seems a bit...awkward. Maybe not though.
I don't see any problem here. Subclasses are just containers for some features that could have been class features instead. If you are at level N in your class, you also are level N in your subclass. There is no option not to get a subclass (although there will be one suggested "Basic" subclass for each class) or to get it at a certain level, therefore it doesn't have any consequence on multiclassing at all.