For a general-purpose superzoom, the DA18-250 is hard to beat. And although it's no longer in production, it (or its Tamron near-twin) ain't hard to find on the used market. I dislike the two-lens kits of 18-55 plus 50-200 or 55-300 (or my 60-300) because I shoot a great deal between 35-70mm, and a two-zoom kit requires swapping lenses too much.
Also, think of each lens as your
window on the world. With the 18-250, you have one all-encompassing view of what is around you. With a two-zoom kit, you have two narrower windows, two smaller views. I prefer the larger view when I am just wandering about.
I own about 200 lenses; I consider the 18-250 to be my basic tool, with all the others being specialty items. I value the 18-250 for its flexibility, and the others for their own strengths and peculiarities. I even value the DA18-55 kit lens! But I mostly use that as a test-bed upon which to hang various filters, optical adapters, etc.
My first lens kit, and still my most basic kit, are: DA10-17 fisheye zoom, DA18-250 superzoom, FA50/1.4 for speed and dimness, and the Raynox DCR-250 for macro-like work. If forced to, I
could live without all the others.