You don't know what you're talking about using the word "science". Science objectively means knowledge; That's all that word means, so you're not adding any information by using that word in your message.
Also, all those things that you mentioned are from fictional work all the same, so using the word "magic" doesn't mean much here. You don't normally see people turning into a blue phoenix just like you don't see people creating fire with their legs. Perhaps the words physical and spiritual would make more sense here.
But yes, Sanji's fire is the hottest one, because it's totally blue with plasma, so based on how fire works in real life, it's obvious that it is superior to common orange flames, or to Marco's inferior blue fire with some yellow flames mixed in it, meaning that it's not hot enough to be totally blue.