Two questions: First is Crocodile's weakness to water. Is it possible that all logias have that same weakness but by the nature of their transformations Croc's is the only one that can really be touched? All of the others would either turn it to steam or freeze it before it becones a problem and it would just fall through Smoker & Caesar. How vulnerable would Enel be considering how electricity and water mix?
What is the most limited fruit we've been shown so far? It was Brook's but he's expanded what's possible with it. Could it be the Clear-Clear or the Mark-Mark or are their users just unimpressive in how they utilize it?