Quote: You love seeing beautiful colors in your photos, greens, reds ,blues, all of it is glorious!
Apart from the polarizer, you need to learn to PP. YOu should be cranking your colours to way beyond what looks good and scaling them back to where they pop, in PP. Any modern sensor and lens combination should give you the good to raw material to work with.
Quote: You love to backpack and shoot landscapes.
First thing… nice lightweight compact tripod.
Definitely the DA 18-135 and 21 or 15 ltd. Don't look at the 55-300 unless you also shoot a lot of wildlife. The 21 is probably a better "street" lens and is a great landscape lens as well.
My own purchasing sequence went..
18-55 and Sigma 70-300, both no longer used, although in the case of the 70-300 it still sees occasional use for close up work.
FA 50-1.7
DA 10-17
DA-18-135
DA 21
Tamron 90 macro
DA* 60-250
DA 35 2.4
40 xs (came on my K-01 and almost never gets used.)
SMC- A-400
Sigma 18-250 (A great "one lens on a trip" lens for travelling light, but not often used close to home where we have a large selection.)
Sigma 8-16.
SIgma 70 macro (we have two shooters in the family and need two good macros, for one person, just the Tamron 90 would do.)
Currently I consider very few of the early images taken with the 18-55 or Sigma 70-300 to be useable, although many of them would be great images if taken with a better lens.
If someone stole all my stuff and I got an insurance settlement, the 18-55 and Sigma 70-300 are probably the only ones I wouldn't buy again. I'd take a DA 55-300 instead of those two.
So, all I can say is have a plan, and start with the 18-135 for your hikes.
After shooting for a while, check to see what Focal Length the largest number of you pictures are taken at, realizing that if you have a lot of 18mm images, you probably need a wider lens, and if you have a lot of 135mm images, you probably need a longer lens.
Look at not only the number of images you took, but which ones you wish were better. You might have a pile of images taken in snapshot mode at 24 mm, that are the majority of your images taken, but, they suit your needs and you don't need to improve them, while you have a few images taken at 70 mm, you really wish were taken with a better lens. Those are just examples, not suggestions, only you can make those decisions.
Starting with primes will box you in and not allow you to determine which focal length most suits you. You'll learn to make do, but you won't find what your personal preference is unless you get real lucky and actually buy the prime that best suits your style.
At some point I'd still like to pick up a 31 ltd and 77 ltd. but, for the most part, I'm done. Others have a different list, based on what they do and how they shoot. But as soon as you say hiking or outdoors or travel, the first thing I think is WR and wide range to avoid lens changes. That's the 18-135.
You won't find a more outdoor lens.
https://www.pentaxforums.com/forums/10-pentax-slr-lens-discussion/179869-da-1...at-can-do.html Pentax SMC Da 18 135 mm F 3 5 5 6 DC Lens Brand New 002707517376 | eBay