Room transfers are not a big deal. Call Bell Services, have them come get your stuff. Tell them you are transferring to the DLH/VDH tower. Get your new room, Call Bell Services at DLH, and they'll bring your bags up.
I'd stick with a 1 BR in the villas over the DLH. Do they have any 1 BR in the DLH with a downtown disney view? Also, keep in mind that most 1 BR in the DLH only have one bathroom. There are a few with a half bath as well, but not many! You'll get two full bathrooms in the villas 1BR suite (not sure if that matters or not).
We do early entry at DCA every trip from the VDH tower. It's not as close as GCH obviously, but it's not a long walk. Exit out the VDH tower, cut through the Frontier tower and walk down Paradise Way. Cross the street at Disneyland Drive and go through the Pixar Pier gate. It can actually be faster than going through the GCH entrance (that line can get really long).
Some will make it sound like the walk from DLH/VDH is uphill both ways.....it's not a long walk, none of the walks are long. Walking from the Monorail station in tomorrow land to the security point at the DLH is about a 17 min walk. This isn't WDW where you have to sometimes take a shuttle just to get to your room from check in at some of the hotels! The whole area is quite compact.