One note about sending packages back to the hotel from DL: be sure you have your receipts, as they won't send back anything that isn't on a receipt. I was going to send a few items back that were in my purse (poncho, brush) and my extra sweatshirt (purchased the day before but receipt-less), but those couldn't go in the bag of new purchases and had to stay with me (tip: if they ask you if everything in the shopping bag is on the receipt, say yes). The locations I know of where you can drop off your packages are the News Stand (near the DL entrance/exit on Main St), Pioneer Mercantile in Frontierland, and EngineEars in CA.
I voted for staying on site. It really is nice to be off the "real" streets. If I could save $1000 staying off site, I would likely have a different opinion, but rarely have I had enough of a cost difference (thanks to AP rates and good timing) to tempt me to stay outside the resort. Last month my sister and I walked all up and down Harbor and over to the mall (Garden-something). Honestly, I found it depressing and was glad to enter the resort and exit reality

. I'll be staying at Hojo's in January because it's a low budget birthday trip and not my main DL vacation, but I'm trying hard to think of some way I can squeeze out the extra money for DLH. I need about $125 more for it. 2 nights at DLH @ $149/night + tax and resort fee = ~$380; 2 nights at Hojos @ Ent. rate of $59/night + tax = $135, and split between 2 people the difference is $122 or thereabouts. Doesn't sound like much, but I have to come up with airfare etc and I've already been in Oct and Nov and am going again in Feb
It's interesting to see all the different opinions. I personally don't like GCH that well. I love the lobby, but much of the hotel is just weird and inconvenient. I do like the CA entrance, but it sure seems like they could've come up with a better hotel layout. I don't find it worth the money unless I'm splitting the cost and/or on an adult trip. I like Whitewater Snacks but the regular full service restaurants are way too pricey for families, IMO. OTOH, I wouldn't normally stay at PP when for slightly more I can stay at my favorite, DLH. I like staying in the Dreams tower, which makes it convenient to get to DL either by walking or riding the monorail. I like the restaurants on site and I like the bookstore & RFC steps away. I won't say I'm wild about DTD but I do like it much, much better than walking down the sidewalk outside the resort, although I can't stand the kettle corn smell after about a day.