Buying a D300 over D700 purely because of the 18-200VR - stupid?

Seeking some opinions from the peanut gallery on this one. . .

A bit about me- I'm 30 and got into photography in April of 2007 when I bought a used D70 and Tamron 18-200 lens. Later I added the 50mm 1.8, which I just upgraded to the 1.4, and this is the lens that seems to be on my camera most of the time. I also have an SB600.

Money is not really an object as I consider this stuff an investment, though spending less is always better, especially as far as my wife is concerned.

I have a wife and two kids (5 and 2), and they are who I take most of my pictures of. Many are indoors, which is why I like the 50 so much.

I've been oggling the D300/18-200 VR package for a while for it's many improvements over my current setup, but I preordered a D700 on July 2nd from Amazon so i could 'think about it.'

At one point I was all about the D700 because I figured I could take lots of clean high-ISO shots of my family in even DARKER indoor lighting, but then I realized that my ONLY lens for it would be the 50 1.4, and that there is no FX equivalent for the 18-200.

Any other lens I want, i.e. the 24-70 2.8, is gigantic, way expensive and not nearly as versatile as the 18-200VR for traveling, etc. I guess I could get the 70-300VR, but it's not the nice all-around travel performer that the 18-200 is, and I do travel occasionally and want to have an all-around.

The more I think about it, I am going to need a DX body no matter what, and I really don't want to use my D70 anymore. I kind feel like I have no business getting a D700 because I have almost no glass, and the glass I COULD get still doesn't fit that 18-200 niche.

So here's my plan - get the D300 kit ($2200 on Amazon), then start buying all FX compatible-glass for when I eventually go FX, probably whenever that mystical 24MP FX sensor makes it's way into a D700ish body.

Is this stupid? Should I just get the D700 now? Thoughts???