If I count correctly, you are on your eighth camera within 2-3 years, and I understand that you are kind of getting tired changing cameras. I believe that there are three components necessary for photography. In order of importance - skill/interest of photographer, type and quality of lenses and finally quality of camera/sensor.
In case it may help you, here is my upgrade history and reasons why I changed cameras:
2004: D70 - added 70-200/2.8 to get better reach and IQ 2006: D200 - D70 needed to be repaired, also liked the higher resolution and better built. Replaced the kit lens with the 24-70/2.8 2008: D700 - I like wide angle photography and wanted an FX camera to better utilize the 14-24/2.8 lens. Also liked the high iso capability. 2013: D800 - Had acquired some very good Zeiss manual prime lenses. Wanted the high resolution and better liveView performance to fully utilize the superior capabilities of the Zeiss lenses.
The D70 is still in use with the 18-200 DX lens after conversion to IR. I still use the D200 because of its longer reach for telephotos The D700 continues to be used with the Nikon f/2.8 zoom lenses.