It sounds like the K-7 will fit your needs quite well. I think the K-7 is phenominal outdoors, and at least average indoors. I can't say anything about the DA* lenses, but I got the two kit lenses, the 18-55 WR and the 50-200 WR because I wanted to have a great, light setup for the outdoors. These lenses take good pictures and if they are damaged on a rough outing, they could be replaced as compared to a DA* lens. I have not been disappointed. The DA* lenses are supposed to be better and that thought makes me giddy because the kit lenses on the K-7 can take amazing shots.
To answer one of your questions, yes, the K-7 is very weather-resistant. I have been caught in two heavy storms with it so far, and the camera and lenses withstood everything.
The other thing is I think the K-7 continuous autofocus gets a bad rap. For outdoor photography (non-sports) you won't use it a ton unless you shoot birds in flight. Honestly, I was surprised recenly while shooting some birds at the beach because from what people say about the K-7 focus, I shouldn't have gotten many keepers. The majority were keepers. You can see the continuous autofocus shots
here if you care to.
Of course the K-5 has to be even sweeter, so if you have the patience and the money, I say go for that. But going with the K-7 now is not a shabby choice either.
Good luck with your decision!