Do note that jacking up the aperture to f/16 and beyond for a crop body is not advised due to the problems of diffraction.
Also, since you want lenses that give you a long range, why not consider the 18-55mm IS with the 55-250 IS? Decent price overall and both lenses are very compact. You gain IS which is a very expensive function in Canon's lenses plus they are of a higher quality and built even then any of Sigmas' or Tamrons' offerings in the superzoon arena.
Of course if you're lazy, you can get one of what they have and wield it on your DSLR. I'll then recommend you get a D40/D60 and the 18-200 VR. That would be the best compromise overall IMO.
Samuel