Sorry to comment and then run, but I think we just have different levels of what we're comfortable with accepting at Disneyland. I'm sure nothing I think hasn't been said before or would convince either of you I'm right.
I agree this will be the first land at Disneyland based on one IP. I think what it boils down to, is that I'm okay with that, and not everyone else will be.
But to comment on why WDW isn't building behind Frontierland, they have a park that is in trouble and needed to attract more people. I think it's as simple as that.