I'm not sure what the zoning is in Anaheim as far as how many stories high they can build, but I'm really surprised, given the small footprint of the area, that they've used so many flat lots up until now. I mean, for crying out loud, the Car Dealers in the O.C. have parking structures as showrooms to save as much as possible on lot footprint.
I would imagine that DLR would consolidate a lot more parking into structures to save the open space for expansion.
It surprises me how much flat space still exists in the form of parking in and around the block area between Walnut -> Harbor and Katella -> Bell!
There is absolutely enough land there for an additional park (not that I'm particularly endorsing it...)
In particular, the lot at Katella and Walnut boggles my mind - it takes up so much footprint space that could be used for all kinds of things. I think about what DLR charges for hotel rooms, even for Paradise Pier, and think that even if a third park didn't make sense or wasn't accessible from that location, they could easily get away with building an additional resort and banking off of that. WDW builds resorts like crazy and gets primo $ for them even with tons of rooms. With so few rooms at DLR, there's no doubt that they could profit handsomely from a fourth resort!