Stuck deciding: K30 or D5100 (or K5!)

I’m stuck in making a decision on a first DSLR.   I’ve been reading through reviews and threads for a while.   I think I am down to the Pentax K30 and the Nikon D5100 (although it nags at me that maybe the K5 might be more durable and the most bang for the buck).  The camera will be used both for indoor photography as well as kid’s sports and nature/wildlife photography.

I honestly had been leaning towards a camera I could buy at Costco because I live on an outer island of Hawaii and shipping costs for returns and repairs can be a big deal.  Costco sells a K30 bundled with a point and their shoot WP camera and the 18-55mm f/3.5-5.6 AL Lens (not WR) or  the D5100 with kit lenses 18-55mm Nikkor AF-S DX VR and lens 55-300mm Nikkor AF-S DX VR lens for essentially same amount of money, $800 to $850. A non-Costco sourced K30 with a Pentax 18-55mm f/3.5-5.6 DA AL WR lens seems to be around $700 or bundled with that and a Pentax 50-200mm f/4.0-5.6 AL Zoom Lens hits at the same price range as the Costco Nikon kit.  Going up from the Pentax 50-200 mm to a 55-300mm or going with a single 18-135mm WR lens adds about $100 to the K30 kit.

I am leaning towards the Pentax line, even if I go outside Costco, in large part because the IQ seems potentially better and they seem more durable than Nikon?  The camera will be taken out in boats, beach, hiking, camping, and in the rain esp. during trips back to Pacific NW.  It seems as if weatherproofing is a good idea, but Nikons are obviously used extensively outdoors so perhaps this should not be a big decision point?

The other advantage I perceive of the Pentax is the viewfinder and better fps for sports action.  It also seems that the in-camera autofocus might  allow using older/less expensive lenses?  However, the two kit lenses with the Nikon (or non-Costco k30) might enough for quite a while to nullify this point.

With the exception of the missing external mike jack for the K30 is the video performance of the K30 and D5100 largely the same?

For the Pentax, does using a non-WR lens compromise the WR body of the camera, i.e. if I shoot in the rain with a non-WR lens can I damage the camera itself or just the lens?

For the Pentax or Nikon  is there an advantage (given the variety of uses I’ve decribed) of opting for a single 18-135mm lens in place of the typical two lens kit, e.g. 18-55mm and 50-200mm?

Any comment on the lingering gut feeling that the K5 might be the best overall solution?  I’m assuming that as a novice, recreational photographer I am not going to notice the difference between the k5 and k30?  I like the slightly higher frame rate and buffer of the k5 (than K30) for sports, as well as the metal body and possibly better ultrasonic/self-cleaning.  However, I have read about issues with the K5 autofocus and it sounds as if overall the K30 might perform better on the focusing front and for the limited video I might take.  This is what I am telling myself....I'm open to reconsidering.  The K5 appears to be around $150 more than the K30 with same 18-55mm lens kit.

Final question.  If I end up not working with RAW files and using mostly for JPEG is one of the above cameras going to provide markedly better output ?

Thanks in advance for considering this lengthy list of questions.