Crossword Puzzle Well-organized person

Clue: Well-organized person

Organized person's motto (it's the puzzle theme!) (FIRSTTHINGSFIRST with 16 letters)
Thin person's sobriquet (TWIG with 4 letters)
Person from Muscat (OMANI with 5 letters)
Person of higher rank (ELDER with 5 letters)
Really thin person (e.g. SCRAG with 5 letters)
Greet a person casually (SAYHI with 5 letters)
Personification of the wind (AURA with 4 letters)
Personal creed (ETHIC with 5 letters)
Darling person in "Peter Pan" (WENDY with 5 letters)
Wonderful person, as it were (GEM with 3 letters)