Luna needs a friend

I think Luna needs a friend. I think she's becoming bored during the day and has way too much play energy for me when I come from work - there's only so many hours I can play with her - but she never seems to wind down.

And lately I've found her destroying things on the nights my boyfriend is home and has locked her out of our bedroom.

SO I've been thinking of getting a cat from the Cat Protection Society or some other shelter - of course, after trying her out with them to make sure she gets along with other cats.

So I have a few questions.

Luna is a 6 month old, very playful female.

Would it be better for her to be paired with a male or a female (she is spayed)
And should I get one that is older than her, same age or younger?

I would like her to calm down a bit, or learn to be gentler (I got her when she was 4 weeks old and while I managed to get her to stop using claws when playing, she still bites way too hard than she intends to), should I look for a cat that is playful as well or one that is a bit more laid back and quiet?

I guess I'm worried the wrong choice would adversely effect Luna and I'm just trying to do what's best for her.

I also thought about fostering cats and kittens, but I'm worried that bringing new cats in and then having them leave and then getting more would be bad for Luna..

There is something really great about two companions who are in the same life stage. I would look for a companion who is similar in size, temperament, and energy levels where the two of them can go through life together on roughly equal terms. I personally think boys and girls have different attitudes and like having same-sex extended families, yet I am sure there are many who have success with mixed-sex arrangements.

How do you know if they are lonely or just growing up?

Should a 9 month old just be waking up to eat 5 times a day as it main event,growing out of playing with you already? Mine is also abit destructive at night knocking items over, suddenly chewing stuff.