The casting for all the films is fantastic. Anybody who thinks otherwise can shut their mouth right up.
I dunno. The casting of Orlando Bloom for the character not appearing in the book was odd.
You don’t tell Legolas what movies he can and cannot be in. Legolas does what Legolas wants.

Legolas does what Legolas wants.

including a woodland elf maiden that has a thing for dwarves. (Who might have been not in the novel either)