Also, because the material is a liquid, Lumiere can spread it on already existing objects and cover them into an lcd display that he can more or less program.

(And yes, that does extend to other living people. I can imagine a neat vr visor made directly of lcd haha)
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He can also make an object from scratch but it takes some concentration to maintain and is basically temporary.

He can handle a lot of objects, but it's technically just more efficient to use already existing stuff. (Maybe there's just only so much memory to spend programming external displays haha)