Hi Amanda,
I upgraded from the K200 to the K70 in July last year.
Both are excellent cameras, but the K70 is a big step up in low light performance. I'm able to safely run at ISO 6400 with no need for corrections.
Able to do fine focus tuning for all my lenses on the K70
Auto focus is quicker especially in low light situations
More flexible rear LCD screen for those hard to get at shots
Live view, horizontal and vertical guides for shooting
Better bracketing, the list goes on and on.
Colour rendition is as good as the K200 and you won't be disappointed with it,
Only Con - you may miss the ability to use AA batteries.
I love both of my cameras and will not retire my K200, but the K70 is my first to grab now.
Greg
Last edited by Greg1956; 12-29-2018 at 04:15 PM.
Reason: update