@Captain:
What, no love for the Sand Sand Fruit?! Now, I know it's easy to go right for lightning, or ice, but hear me out… For one thing, the Sand Sand Fruit is the only one that can counteract its one weakness; absorbing the water. Not only does it have one weakness (as was mentioned before, other Logias have the sea weakness, and the opposing element. Sand Sand just has water), but a skilled user can absorb the offending water. While the fruit is the epitome of the concept of the user's skill affecting its power, everything we saw indicated that the vast majority of the fruit's uses were either cataclysmic (summoning sandstorms, which can grow more powerful than tornadoes), or fatal (the Desert Spada was pretty much a OHKO). Between the drying abilities one gains by mastering it, to the use of large amounts of sand, the Sand Sand Fruit definately belongs on the top tier of Devil Fruit powers. I mean, hell, it can pretty much take on/out all the other Logia's we've seen...
Fire - Extinguish by suffocating the flames with sand.
Smoke - Create sandstorms, with the generated wind dissipating the smoke
Ice - Absorb the moisture (not entirely sure here)
Lightning - Sand is ground. Absorbs the lightning.
Darkness - If Ace's fire spears did a number on Blackbeard, imagine the damage one would take from a Spada-like attack with that whole increased damage weakness. Especially against a largely fatal fruit.
Now, I don't think there's any ONE top fruit (OP lacks a vertical power ladder, after all), but c'mon! No love for the sand?! Have we forgotten the monstrous power wielded by one of OP's biggest villains?!
I thought of it but remember…
Fire can melt sand.
Smoke…well you can't really do anything with these two against each other except with the wind thing you said.
Ice I thought about this as well. It depends because it seems like with these powers you can absorb the Ice or the ice can freeze the sand.
Lightning This is interesting because actually when some sand is struck by lightning then it turns into a fulgurite. This would end and Suna Suna no Mi user right there.
Darkness This depends on the user of the fruit. You don't want to get hit with the Desert Spada because it looks strong enough to cut off limbs completely.
Crocodile used his powers to an excellent degree and he was very dangerous. No doubt about that. His fruit is an excellent one, but I believe that it can be beaten out.
@nickel56:
But I think it was mentioned earlier, which I agree, that Suna Suna no Mi is highly weakened in a non-desert area. Like, where is the df user going to get so much sand to summon a sandstorm?
Also, the opponent will have no trouble doing what Luffy did, carrying a water barrel in the fight. Especially since it's not in a desert, there will be plenty of water source around.
Well, he fought pretty well on top of the Castle and there was no sand. As was said before, Logia users can summon unlimited amounts of their elements form within their bodies.
Also, how would a person know to bring water? Luffy only found out when he was virtually dead and that knowledge wouldn't help you much at that point. Plus the dehydration ability is nothing to laugh at.