Are the words in brackets OPTIONAL whch word to use?

Could you tell me which word you would use and if the word in brackets are optional?

- Eating in cost less/is less expensive than eating out.

- She lives in the same house as me./I do.

- She makes more money than the amount of merchandise we sell./than what we sell.

- These jeans might look good on you but it all depends (on) what you wear it with.

- You know your husband loves you when he wants you to be more comfortable than (he) himself.

- I know you well for (someone who's known you) 3 months.

- Why do you keep talking about that. I don't see the connection./what the connection is.

- In his movies you never know who the good guy is and who guy is/who the good and bad guys are.

Thank you