I can't tell you why Oda chose to make those Paramecia's instead of Logias because that came down to Oda's choice. Those being Paramecia don't refute Trebol being a natural Logia. In fact, none of the Logias are actual forces of nature. Magma isn't a force, electricity isn't a force, light isn't a force. The only Devil Fruits that represent actual forces of nature inherently are the Gura Gura no Mi, Kidd's fruit and Issho's fruit. All Paramecia. Also, Issho's fruit, Kidd's fruit, the Gura Gura no Mi couldn't be Logias because they create invisible things. If Oda drew them transforming into what their Fruits created, they would disappear from sight. The Horo Horo no Mi creates ghosts, which aren't an element or material of nature.Aspect of nature? Then why did Oda choose to make Doku Doku, Gomu Gomu, Kage Kage, Nikyu Nikyu, Horo Horo, Gura Gura and Ishi Ishi no Mi's (AND Jozu's, Isshou's and Kidds Devil Fruits) Logias? They're all aspects of Nature, in fact all Devil Fruits are an aspect of Nature in the One Piece universe.
What is it that the Logias have that they don't? Force of Nature or Elemental status. I'm clinging to this because you cannot refute it and have failed to, consistently.
Your argument here is invalid as all Logias are different whether it's Smoke, Magma, Lightning or whatever. What makes them the same type of Devil Fruit is what they can create and become, elements and forces of nature (as perceived by Ancients).
And yet they're all forces of nature/elements except from the bolded one.
You clearly didn't understand what I was saying, so I simply wish to elaborate: Fundamentally, all Gases have free particles that will all fill a container, they have abstract shape. This is similar to say Magma (which is all superheated ash and rock), smoke (all a biproduct of a fire), fire (all oxygen + ignition to an object) etc. However, Mucus (like Wax and Poison) isn't all fundamentally the same. Mucus comes in many forms from living slimes to adhesives to snot to sap, all of which are very different, perhaps only sharing one thing in common, they're sticky. That's it.
However, people could say metal is a part of nature and technically Baby 5 creates and become different metallic objects. This is where things become blurred and the differences between these types of Paramecia and Logias become less defined. One of the reasons for such a debate.
Caesar can however, do this:
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Which is his genuine element form. The mucus carries the stripes and circles and markings from his jacket anywhere and everywhere. If he makes a rope, it's marked with the same markings as his clothing rather than looking like normal slime (which is not what you would normally expect from a Logia). It's similar to Crocodiles sand being the same colour as his clothes, carrying weird stripes and fur around, or Enels lightning being a pale colour, and having nipples should he launch a "thunder beast", or Smokers smoke having abs and the pattern of his cigars forever in the colourscheme of his smoke.
giostep already refuted your point about Baby 5.
Like I said, their transformations can retain the same color as their clothes through partial transformations. Trebol has yet to make a full transformation into his fruit, and that's why the ring patter on his clothing is retained. In the picture of Caesar above, he clearly retains the pattern that spells the word "GAS" on his outfit, despite his clothes being in a state of transformation. Your point about Trebol making ropes that keep the pattern is actually very incorrect. His Beta Beta Chain lacked that trait.
Look at this picture of Kizaru for example. It shows his suit in a state of partial transformation and no transformation. And lo and behold the color is the same. Pattern it has is the same. Just like Trebol.
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