Yeah. It's like how much money do you want to spend?
That's why originally I was only looking at spending about $600 or so to update myself from my Pentax K100d to a Pentax K-r. Maybe a bit more to get an autofocus lens that went up to 200mm that was faster than my superzoom to give the camera a chance to focus at that focal length in poor lighting.
The two things with my Pentax K100d are that I don't think it focuses fast enough to keep up with my daughter and it only goes to ISO3200.
I was looking to pinch my pennies and see what the cheapest camera I could get that I could squeak what I wanted out of it.
Which sounded like what you were looking for in your original post.
If you have a store close to you, it won't cost you anything to try your lenses on a K-r or K-5 to see if it focuses faster. Is it fast enough? I don't know. I was just about to find out, but then my wife came to me and said, it's time for you to get a new camera, here's a budget. I guess that's my winning the lottery. <grin>
Anyway, good luck on your camera hunting!
And happy shooting!
Take care, Glen