Personally I like the classic looks best but the GTC is a nice car as well. Problem is they built these cars in less numbers than they did with the GTE and 330 GT (I guess 500 to 950-1000 of the classics). This means they are very hard to find (at least here) and if you are lucky it will be a good one but it can even be a basket case. I think the GTCs are less well taken care of than the GTE and GT 2+2 in general, having undergone an excellent restoration job at least once in their lives. Although I am no expert, I think it might even be harder to find proper parts for the 365 range. Don't know the market prices of these cars today, but I have to admit I did not even think about those in the first place ;-)
NIels