You'd likely need to increase the page count either 16 or 32 pages, which, once you add in the Artificer and the Psion classes, would fit quite nicely
What I really don't get is how it makes and current PHB worthless. They didn't change any rules, they added additional ones to it. Adding this to new printing of PHB no more makes the old ones worthless than putting the rules into another supplement does. But it does mean that every new player gets these choices at their entry point to the game, and gets around PHB+1 issues for AL.
It does harm the resale value, which WotC has said they are very concious of in the past when asked about modifications to the PHB. They want the PHB to be a constant.
Don't expect anything except minimal errata in the,PHB until 6E rolls around. Indeed, at this point, don't expect any new errata for the book.