I would also add that imho all 3 of the Disney hotels are close to the Parks. Grand Californian is definitely closest since it has direct access into DCA. DLH is a short walk to the monorail which takes you into the heart of DL, not just the main entrance. It's also just a slightly longer walk from DLH through Downtown Disney to get to the main entrance for both DL and DCA.
i think you just need to decide if the concierge splurge is worth it, hehe. If it were me, I'd go concierge at DLH just because I love the idea of it.

The Grand Californian is beautiful, but I checked out my friend's room there about a year or so ago, and it looked pretty small imho.