An alternative to huge D2X files? discretionary use!

Is anyone using the lower resolution settings much?
For the majority of shooting I suspect many/most of us don't need the wonderful-to-have 12+ mp capability.
I keep reading of storage woes and long processing times.
Lest we forget how perfectly adequate our prior cameras were...I'm thinking of it thusly.
Large 12.4 MP wonderful to have.
Medium 6 MP setting equal to an improved D1X.
Small 3 MP setting analogous to an "antique" D1.

6 MP is more than enough for handheld shots of my daughter's friends. Handheld at 1/60th...whats the use of 12.4 MP anyway.
Snaps of my wife's social function for her medical society newsletter reduced to 3 inch B&W 3 MP is more than adequate.

I love options. For lots and lots of stuff huge files are superfluous IMHO.

Anybody else using this sort of discretionary file size selection?

12.4 is heaven with great light, fast shutters, cropability, critical use etc. but...How often do we employ all the horsepower of our vehicle?

Ideas anyone?