Quote: Read enough disappointing reviews of the kit 18-55mm lens to pass on that but not sure where to turn.
Don't believe everything you read. The Pentax kit lens is quite good and will deliver images far above what you are getting from your pro-sumer. Is it prime lens quality? No, of course not, it is a $100 lens, Pentax's DA*16-50 with roughly equivalent range costs more than $1,000.
Quote: The reviews for the 16-45mm lens are really good but I don't understand why it is not mentioned in the K-30 Lens lineup here on the forum?
The reviews for the 16-45 are generally good but this lens is often over shadowed by the DA*16-50 and the Sigma and Tamron equivalents @ f/2.8. I think a lot of people when moving up from the kit lens just go all the way to the f/2.8 models and skip the f/4 lens, so it does not get mentioned as much.
Quote: The 18-135 mm lens seems a good choice for a walk around lens but there are just as many negatives mentioned as positives.
There were some initial reviews that did not rate this very well, possibly people were expecting too much, or maybe the initial runs had some QC issues. But I rarely see anything but good reports now. I have some very good primes but this is on my want list for a vacation zoom. It may not be top of the line but for the price and range it is hard to beat.
Quote: Am I better off getting a 200mm or 300 mm prime lens for when I do wildlife pics?
Better off? Maybe, but long primes also restrict you to a particular distance depending on the subject. If your subject walks towards you, what do you do? But image quality will be best that way. I would take a look at the DA 55-300, it is very good within it's limitations, slower than the primes that will reach there and slower to lock focus than I like but for the price it is an absolute steal.
You ask a rather simple question but really only you can determine where on the quality / budget curve you are. If you are in this as a business and image quality is the only thing that counts, or if budget is just not an issue, then lot's of people here will be delighted to help you spend money. Lots of good glass out there if you have the money. But otherwise, everything is a compromise, how much do you want to spend for what quality? Just remember quality is not a linear function of price. The DA*16-50 costs at least 10x the DA 18-55 but it is NOT 10 times better, as the lenses get better they get proportionally more expensive as it gets harder to improve them.
If you want my suggestion get the kit with the 18-135 and add the DA 55-300. That will give you a great starter kit that will cover just about anything you want to do. If you see an area you want to add to you can do that as you learn what lengths you shoot at more. Add a Sigma 10-20mm and you have 10mm to 300mm covered in three lenses. That's a pretty complete kit for general photography.