24mm will still not be wide enough on DX. I have a 24-85 that I had on my F80 film body and then bought a D40 with the 18-55 kit lens. For a lot of scenic shots I found myself reluctantly swapping to the wider kit lens as the 24mm just does not do it. With these two lenses, I was always frustrated to let shots pass because I did not have the reach but now I can take those shots, I use my 70-200 less than the wide 17-35. I think you need to be able to shoot wide to at least 18mm on DX.
The path from DX to FX is not easy as for the most part the FX lenses will be the wrong focal length so it will be a compromise.
If I was going to buy DX from scratch today and budget was limited, I think I'd get the D7000 with either the 18-25 kit alone or get the two lens kit with the 55-200 kit lens in addition. The reason I say this is that I could not pick any difference between the kit lens and the lens I paid $800 or so for in photos I took.
Then, I'd suggest getting one low light lens and I'd go for the 35mm f1.8 which is cheap enough to trade out of down the track. My next purchase would be a wide and if I was going to stay with DX, the 12-24 would be the way to go. Later, grab the 18-200 and you are done.
If FX was in the future for you, get the 17-35 f2.8 followed by a 70-200 f2.8. When you finally had the coin for an FX body, trade out the 35mm DX and replace it with a 50mm f1.4. You should only be out of pocket $100 or so on the changeover and you should have captured some great pics at 35mm to compensate for the loss.
The FX strategy is the similar path to I took. I deliberated on the 35 mm vs 50mm decision and wnt with 50mm which I think was the wrong choice but my pending D800 will fix that.
I think this strategy would maximize your investment in DX and only see you spend the cash when you were really certain FX was the way to go after taking at least 10-20000 photos on your DX camera.