I agree with DeeP's description of the lovely, homey accommodations of the onsite DVC 2BR timeshare villas. Here's the rub: They run about $400 per night plus taxes and UP. Even a DVC points rental from an owner would still cost you $220-$300 per night for a 2BR (midweek only, in Jan/Sep/early Dec only) up to $1060 per night (Christmas/Easter weekend nights).
There are very similar 2BR and 3BR timeshare villas offsite for well under $200 per night. If you rent by the week, these 5 Star and Gold Crown offsite villas are readily available from owners for about $700/week or less than the rental of a DVC villa for just 2 nights. They are offsite and that's the thing. Offsite vs. on. Car vs. Disney boat/bus shuttles. Steel drum or pop or beach tunes vs. Disney songs at the pool. Pool hopping or your resort pool only. Friendly service vs. Disney costumed CMs. Local restaurant prices vs. Disney food prices.
It's always cheaper to get all that space & luxury described so well by DeeP, offsite. So if you think you'd really miss the "Disney-Disney-everywhere" feel, then expect to pay for it and go ahead and enjoy it onsite. This is especially true if you spend more time outside your room at the resort, and want to see Disney themes all the time (or if you won't have a car). If you are looking for relaxation, space, privacy, luxury and family fun in your villa, that's not necessarily Disney themed, when you are outside the theme/water parks, you'll definitely have options offsite to fill the bill for much less money. Hope that helps.