I can think of one thing. Paramecia are said to produce their element/DF(Doffy produces strings, Foxy produces time slowing waves Fuji produces gravity etc.) but Luffy doesn't really produce anything and his body is always rubber whereas Doffy's body isn't strings and Fuji's body isn't gravity(which opens the paramecia/Logia door on the Gumo but that's neither here nor there) so what if his "awakened" form allowed him to produce rubber from his body as most paramecia do? To me this would be depicted as Luffy being able to produce and control rubber tendrils from anywhere on his body, sort of like Venom.
something like this
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Luffy being rubber could change the shape to make it so he has multiple fists, imagine his gatling type attacks with an extra dozen hands flying. Or he could shape his rubber and make it long and thin then coat it with haki making it like a blade of sorts.