We went about that time last year, and it was great. I was wondering if you are avoiding MLK, which can add crowds, and you are (it is 1/19).
That being said, I'd still have a plan.
When we go, we do use a touring plans, even with the low crowds. I get input from my kids (mostly the older one since the younger one was 2 and 3 each time), and I make a plan. I do have to explain that we need to do this now, etc. and why (esp. for those more questioning kids!). I think that if you prepare them and get their input (use books, the vacation planning dvd, and the official Disney web site so they can see what to expect), a touring plan will work. Just make sure that they know that you have a plan and will fit everyone's desires at different points.
I think that having a plan can also help avoid arguments. If everyone knows that there is a plan, you won't have four people requesting four different attractions. And you aren't having to take time to decide among four people each time you get off a ride. I use the Unofficial Guide's web site which can tailor plans to your needs (e.g., touring the MK with girls 4-9). People also like Tour Guide Mike (which I might try next time for kicks!).
Have a great trip!