Wahoo! Thank you all for your answers!
I'm happy I have joined this forum, and more than happy to get my K10D as soon as I can find one (not so easy here in France — or Germany —, at a good price).
I'm impressed by roy images. Superb quality, roy! I might consider to juste take the kit lens.
About the Sigma 17-70, yes, that is one I already considered. f:2.8, plus the stabilizer, should help shooting in low light without a flash (I do not like flashes very much — so, the second resaon Jacob gave for not taking the 16-45 is not very strong for me.), and the focal range is very close from the Nikon kit lens (which is very good).
The choice is even more open now! Thanks again!
PS: and there is the Tamron. 18-200 is very very transstandard. A little bit like the Nikon 12-800 VR. Could be a good choice for an (almost) every occasion lens, with more specialized lenses in the future...
But what about tropicalization?...