You've given no indication what you shoot or why you think you need an FX camera.

FX is better than DX at some things... But it's worse than DX at others. "Going full frame" never made anyone a better photographer. But it can be the "right choice" for some things... Or the "wrong choice" for others.

#1.... You WILL need FX lenses, which tend to be bigger, heavier and more expensive. Yes, the camera can use DX lenses... but you'll end up with approx. 10MP images that aren't nearly as good as what you get now from your D7100.

#2... Unless you make big prints from your images, you will see little difference in your end results. Yes, images may look sharper on your computer monitor while viewing them "at 100%", which is far larger than you'll ever actually use them. On most modern computer monitors at their native resolution, "100%" is roughly equiv. to viewing a five foot wide print from about 18 or 20" away. Do you plan to make 3.5 x 5 foot prints? By the time you resize the image for "real world" uses, much of the "full frame goodness" will have disappeared.

Yes, there are things FX are good for... such as low light/high ISO shooting. It also can give you more control over depth of field, with both shallower effects (large aperture) and deeper effects (small aperture) than is with a crop camera.

I use both full frame and crop cameras. If I could use only one, had to give up the other, I'd keep my crop cameras and give up the full frame.

Crop cameras have greater overall versatility.... I shoot a lot of sports and some wildlife, where the croppers have an advantage. They also are fine for most portraits and scenic photography.

I originally added a full frame camera mostly for its low light/high ISO capabilities. However, newer crop sensor cameras I've upgraded to in the year since are able to be used at higher ISO than was ever possible with that older full frame camera. I'm sure a newer full frame would be different, but can't really justify the cost of one for as little as I presently need it (probably 95% of my work is done with crop sensor cameras). I prefer the full frame camera for portraits, scenics and some macro work. But I could live without it and "get by" just fine with crop sensor cameras, so that's what I'd choose if I could only have one. I'd never "trade in" my crop cameras for a full frame model, unless what I shoot were to radically change.

Disk space is cheap, so I recommend using mostly JPG from the camera, but saving the RAW with it, though it depends on the kinds of shooting you times do. If you tend to take a lot of pictures or like to shoot quickly, the slow write speed of the P7000 might bother you. Obviously, if you tend to compose more carefully and take your time, a camera that is slow between shots won't matter so much. I mention it because I don't have much time either, but when I do sit down to review whether I have anything worth printing (being an occasional hobbyist) more times than not I wish I had the RAW if it's not there. At least for me, it matters most for dynamic range, such as saving the blocked highlights and lost shadows that the camera leaves in the JPG.