How does the handling of a NB Sport compare with an NC Launch Edition. Assuming all the shock absorbers and springs are in good order and tyres are the same type.
My advice would be to go and drive both, I was sure I wanted an NC sport, until I drove one and was completely underwhelmed, the 1.6 NB I drove an hour or so later whilst slower just felt more like a sportscar. I ended up with a 1.8 NB and love it, plus the handbrake is in the correct place in the NB and in the wrong place on the NC. 
I was the same, but after changing the springs, ARB, and put Nankang ns2r tyres on it. Much better than a MK2 now
AS above, you need to drive both, I have both and they are totally different.
Try adding a location to your profile, you may find someone willing to take you out in their cars.
Can’t comment on those specific models but having just bought a NC to replace(?) my NB I have to say I find the driving experience of the NC slightly better so far. The steering on the NB feels much lighter and a little more jittery than the NC, although lower springs and a few other suspension mods might sort that out. By comparison the NC is firm and when you point the car into a corner you know it’s going to go there. I’ve yet to give the NC a run on twisty country roads to really test the handling although I’m hoping to do that this weekend. What I can say is whichever one you drive you will have a smile on your face!
Having had both the NC and NB I personally much prefer my NB Mk2.5.
Having upgraded the NB to the NC recently I have found that they are really separate cars. The NB is the more “Balls out” spirited sports car where as the NC, To me, is more of the GT type. Personally I was looking for the more Tourer type anyway as this is my preferred style. The NC is more refined and civilised, the NB while it wont nut yer gran and rape your pet, its more sports focused than the NC. Have also found that the NC if slightly more practical, having the larger boot but you really do need to drive them each to appreciate the differences
I would agree with this, the ND takes you more into NA/NB territory too. I had 2 NC’s and enjoyed the cars before and after more.