I can relate to your thrifty nature...
We bought in 12 years ago as a group with 3 other family members and had just 55 points for our own use initially. We used those points to stay in studios for a 5-night stay each year. We cook most of our meals in the room, which we prefer in addition to it being much cheaper. We once combined points and stayed in a GV - that was fun.
A few years ago, we added 55 points, primarily so we could stay in a one-bedroom. Our kids are getting older and so the extra space made it more of a vacation for everyone. Now, we find that we are visiting every other year, as the kids' schedules have gotten busier. Our 110 points allows us to stay 7 nights, so we stay a bit longer and don't move for the weekend. We find the dues to be manageable - even if I add up 2 years worth of dues, it's around $1000 - a lot less than it would cost to stay in most of the on-site hotels, and we get much much nicer accommodations. We buy the 10-day non-expiring tickets, and get 2 1/2 trips out of them (4 park days per trip). We like to take a few days just to enjoy the resort and relax.
I'm sharing all of this because we have really enjoyed our
DVC membership, and I especially like its flexibility. As our needs have changed, we've been able to use it in many different ways.
Hope you make the decision that is right for your family!