Now I've written a lot about the quality of the Pentax K-01 images, and you can get a nice 3 prime setup for just under $1500. But cheaper still is a Sony NEX with the 5n kit and a Micro Four-Thirds kit based on the Panasonic GX1. With the Sony you'd have to be willing to accept a thin lens lineup. But the sensor is good, and the system plays well with adapted lenses, or so I've been told. And while the Panasonic GX1 is a really nice camera (I've seen some stunning 18x24 BW prints from it), most rate it a step behind the 16MP Sony sensor found in the K-01. 90% of the time the difference won't matter. A step above the K-01 kit in costs are the Olympus OM-D E-M5 kit and the Fuji X-E1 kit. Both have EVFs which of course the K-01 lacks.
Things don't change that much at the top end. The Sony and Panasonic kits are cheapest, but this time the Sony is the cheapest. This is partially due to the lack of a second portrait lens option. The Pentax K-01 sits in the middle (again), and at the top the Olympus and Fuji kits have swapped places, once again partially due to Fuji's limited lens lineup.
Who's missing? Nikon and Canon. Why? At the time of this post, neither has a complete three lens kit available. Nikon is closer, with a 28mm EQ/2.8 and nice 50mm EQ/1.8. All that's missing is a portrait lens, which I think is on their roadmap (a 32mm/1.2 that's ~90mm EQ). Canon's farther behind with just one EOS-M prime, a 22mm/f2.
Each of these kits have their strengths and weaknesses, but each is capable of taking really nice images. The kit that people chose depends upon which strengths and weaknesses they choose. Personally, the budget Panasonic kit looks really interesting. I more or less had a similar kit at one point (GF2 + 14/2.5, 20/1.7, 45/1.8) and it was really quite nice.
At the end of the day, the Quality of the Image (as opposed to the Image Quality) depends more upon the photographer than anything else.