You have been unlucky with the theft of the K-r and the aperture block failure in the K-30. Time for a change in fortunes!
Plenty of upgrade options within budget: another K-30/K-50, K-5, K-5ii, K-5iis, K-S1, K-S2, K-70, K-3 or K3ii. The comparison tool is a handy start for comparing these models:
Pentax K-70 vs. Pentax K-1 vs. Pentax K-3 II - Pentax Camera Comparison - PentaxForums.com
As Bertwert says, the less you spend on the body, the more is available for lenses. If you want to buy new, you can rule out K-30, K-50, K-5 series - any old new stock of those models is generally ridiculously overpriced.
To sift through the various options, you need to work out what features are essential to you. WR? Strike out the K-S1. Two control wheels? Again, strike out the K-S1. No anti-aliasing filter? Strike out K-30/K-50, K-5 and K-5ii. Articulating screen? Strike out all but K-S2 and K-70. Popup flash? Strike out K-3ii. Popup flash with wireless controller? Rules out K-S1, K-S2, K-70, K-3ii. Built in Wifi? Strike out all but K-S2, K-70 and K-3ii. 20 megapixel sensor or more? Strike out K-30, K-50 and K-5 series. 24 megapixel sensor? Strike out all but K-70, K-3 and K-3ii.
At some point there will be a choice to make between a consumer model and a flagship model (e.g. K-50 v K-5, K-70 v K-3ii). As a general rule, for similar money you get more gizmos with the consumer model (e.g. an articulating screen on the K-S2 and K-70, which is not available on the K-3 series) but more durablility with the flagship. Durability comes at the cost of greater weight; the extra heft is good for heavier lenses, but not so good for travel and carrying around. The flagship models (K-5 series and K-3 series) use the larger DLi90 batteries, which provide more power; those models can also be used with a grip. And the flagship models have many small things that make for a more pleasant user experience - like more buttons, better dust control, quiet shutter, better AF, better AWB metering, top LCD, and so on.
Again as a general rule the flagship models are a safer used buy: for example, AFAIK, the K-5 never had the aperture block problem of the K-30/K-50. The flagships can take a harder life better.
To my mind the value buy at present is a used K-3 at around $US500-600. But if you can find a K-3ii for only a little more, that's a great buy too.
Going from a K-30 to a K-3 was a big upgrade. I have got used to the extra weight, and it's good for telephoto lenses anyway. The AF is much better, metering is better, the ergonomics are much better (even the dials are easier to turn), the extra pixels are great for cropping, and the resolution is outstanding. The shutter makes a quiet and satisfying sound after the CLUNK of the K-30. Dust control is much better. It's a much more advanced camera. The flippy screen would be handy, wifi would be handy, but neither is a deal-breaker for me. YMMV.
Then again I've just ordered a new K-S2 as my second camera (to replace the K-30), as a lighter carry-around option (an excellent Black Friday bargain at $A592 - about $US440 - ie around the price of a used K-5iis). Maybe I'll find the wifi and flippy screen ARE indispensible! (More likely, I'll miss the feel and AF performance of the K-3 when using the K-S2.)
Originally posted by jimr-pdx The II variants were the first ones to add extra AF precision for f/2.8-speed lenses.
Same AF system is now used in the K-S2 and K-70.
---------- Post added 11-28-16 at 12:53 PM ----------
Originally posted by lithedreamer I had a white K-x that struck up so many conversations, then my red K-30 that struck many conversations, and I find my black K-1 with the D-FA 70-200 strikes up many conversations, too.
Pity Pentax is going the Henry Ford route: you can have any colour you like, so long as it's black.
Last edited by Des; 11-27-2016 at 06:48 PM.