Good afternoon    こんにちは
Take care    気をつけて
Good luck    上手くいくと良いね
That's too bad.    残念だったね
You're lucky.    ついてるね
Hard luck    ついてなかったね
Congratulation!    おめでとう
I'm scared.    こわい
Look out!    あぶない！
Ouch!    いたい！
Oops!    しまった！

Shuji:

That is very true that dropping 「です」「ます」「ください」「ですか」 would make it even more casual. I didn't consider that though I did know of it. Learning from text books sort of implies that we must use those to create a proper sentence so I believe that is why I didn't think about dropping them altogether. Simply because my mind has created them; 「です」「ます」「ください」「ですか」as needed particles (?). Are they consider particles?
As for the English question; either way works. Close friends or family // close friends or in a family. I personally feel the "friends or family" sounds better but both can be used.

Thank you for the alternatives! I appreciate them. =)

Thank you Allison! I wish you the best of luck in the challenge! 頑張ってね! If you come up with or across anymore casual around the house conversation please feel free to share! I'll add it to the post~