Nikon was marketing D7xxx series as their top APS-C camera for last 8 years until they introduced D500.
D7200 is as good as D500 in every way unless you are looking for sports run and gun kind of photography. At half the cost of D500 I think it is the best value for money.
With the two Sigma lens it will cost you less or same as a D750 with 24-120. It will yield better results than FX D750 + 24-120 f/4. remember the Sigmas are F/1.8.
In all honesty I am buying D500 at twice the cost of D7200, only for its capability of higher frame rate and buffer and most important factor is the buttons layout on D500 is same as D800 and D4.
I go mad when using D7200 and D800 together.
PS:I feel D500 is over valued at $2000. It should be around $1600 same as Canon 7D II.
Thanks a lot Henry and Dada, I will try to check each of the bodies over coming weekends and will decide. Your inputs are surely going to help me in making up my mind.Jiten , you have very good advises here. If I was you my approach would have been different. Always keep in mind that great lenses on shitty body ( and D5100 is a very fine camera) is always better than shitty lenses on great body. Your 1.5 L budget is not gonna suffice , I am afraid. You have mentioned street, portrait and landscape. I would suggest keep your body & lenses. Get the new Nikon 18-35 ( or tokina 11-16 if you plan to stick with DX in near future) and 70-200 F4. You will see an instant jump in contrast, sharpness and colour rendering. That would also leave some money with you which you can use for a 24-120 F4 or the great 85 1.8 AFS G . Also look of for used lenses in forum like JJmehta. Once your lens arsenal is in place later go for an FX body. Just for your thoughts.
I am not sure if I can get a chance to check signa lenses personally in NCR or not. But if it becomes possible then it would be great.