Is it possible that...
luffy could be able to have a liquid form:
as we know luffy is a rubber man(duh) , and rubber can be vulcanised(resembling that of red hawk attacks)
vulcanised rubber makes it almost impossible to melt (or atleast very difficult),vulcanised rubber is in car tyres and things , added with sodium which when it oxidises can become flamable.
take these principles and luffy may be able to become a liquid(similar to logia but probably with a few draw backs), this is because rubber is found in trees in a liquid state.
and using this he could overcome his main weaknesses being blades and haki enhanced projectiles e.g. kizarus lasers,this would make luffy a whole lot stronger!
for example he could change his shape and make weapons out of his body(this could be important later)
sadly this would have major side effects like i said before, natural rubber is less versatile and stretchy, which would mean in a liquid state he would have a significantly shorter attack range.which is why i suggested weapons earlier; luffy could find that a cannon like weapon to overcome the possible difficulties with his attack range , the cannon could fire highly concentrated air (similar concept to the pad cannon attack kuma used) which would probably make luffy a very powerful adversary and a challange even to an admiral.
do you think that oda might incorporate liquid rubber into one piece?