The D3200 is a very capable camera in the hands of someone who is able to draw out its photographing technology. Even professionals use it in some genres of photography when they don't want to carry their large cameras around. So I'm wondering why it is that amateurs eschew the camera. The features that this camera has are great; it's perfect for the portrait photographer or the guy who fancies himself a street photographer or taking those every day shots that you want to document. The only person who would not benefit from a camera like this would be the wildlife or sports enthusiast or professional who needs the fast fps that a D300s (6 fps) has; the larger buffer which means more shutter clicks before the buffer tries to catch up.
The D3200 is a workhorse in a small package. Nikon has boosted the ISO on this little DSLR and that has made it a low-light wonder. You can use this thing for night photography on a tripod. You can photograph indoors in low-light settings, whereas my D50 was so grainy when one put it up to 1200 ISO the photos were unusable. One is able to do a lot of things with this camera.
Which goes again to the simple adage that "it isn't the camera that creates the image - it is you" and nine times out of ten, the problem with blurry photos ends up with the person taking the image and not the camera. An upgrade in camera body is not going to help in creating an image. It is your skills that come into play to create an image that is compositionally sound and tack sharp.
I've always been of the attitude that you upgrade when you have the knowledge of what it is that you expect out of the camera and that the original camera is not meeting those expectations. Otherwise you can upgrade all the way up to the D4 and find out that you're still getting blurry shots. No camera will output what it is that you want until you work on your technique.