By the numbers of the party (6 total), it sounds like you will be in a 2 bedroom villa. This will be a huge step up from a value resort, which shouldn't be missed if at all possible.
With the kitchen for breakfast, occasional lunches/dinners (we like to bring to the pool) and snacks, you will find that you can save a lot on dining and alchohol expences. We always do a grocery run since we drive. For us, it's a lot of fun buying a weeks worth of food and beverages as we usually buy stuff we wouldn't normally get at home. Lots of pool side snack foods and drinks; some of it actually healthy!
The other fun part is planning our ADR's. We have the TIW card so we same some $$, and do enjoy the TS experiances. We usually use TS 2 out of every 3 days we are there. We average about $500 per couple for food/beverages including groceries over a 5-6 day period. Your milage may vary.
My vote would be to go. Life is too short, and this is a an awesome opportunity.
Be sure to budget some 'thank you' gift as DVC points are not by any means 'free'.
You didn't mention which DVC resort you'll be staying at. I'm sure we would be interested, and many of DVC'ers can then offer you more resort specific tips to help you save and better enjoy your trip (yeah you've already made up your mind).