I'll speak of my letters; though you might be confused:
So many to choose from; so many are used.
I sometimes have two, often three, at times four.
Dot if it helps you; for me it's a bore.
I'm known for my seven, my eight, different ways.
I can see that your eyes have developed a glaze!
I could speak of my children, let their letters be thine:
They have twelve, five and six; one has eight, one has nine.
Of the child with nine letters, to some it is known,
It sneakily has 'nother four of its own.
I've known some great heroes, with their fighting and fun.
Let me know when you've got it. I'm awake when you're done.
Although I'm a noun, a person I'm not,
Nor am I a thing. What else have you got?
Another Hint: (for lover of rhyme @Brent Hackers)
When I get a visitor, and when he has been pluck'd
from a burg full of country mice, he'll surely be in trouble.
A lady of mettle welcomes all to my scene
She's tall and she's French and she's def'nitely green.