I like both fortresses for different reasons. The original works much better a toy, the raised baseplates mean that you can build and pack a way quickly and its just more playable. I didn't have the original as a kid, I only had pirates who resided on the outskirts of a large paradisa complex, but I guess it's the same deal - slightly different play scenarios.
I kinda think the new set is a great re-imagining but it's built for nostalgia and displaying, more than playing. I like the fact you can arrange it in different ways... although my partner insisted we had to have it in the original config for the new set up because the big pier is too short to dock one of the big ships and needs extending...
I have a lot of the new bluecoats because I got back into lego just before the 2015 wave came out, so I majorly stocked up on all those set and the chess board. So I like them for that reason, but the readcoats are probably my preferred faction. I like ri have a mix of both old and new, but mainly whatever I got my hands on.