If 90% of options are not exercised, should I write in-the-money naked call?

Absolutely not. Depending on which book you read, 80-95% of all options expire worthless however you want to write in the money calls, which is just the opposite. You're selling people options with a good chance of staying in the 5% category-especially since you're doing it so close to expiration. Also, if they are naked, you need to have a contingency plan in place in case they are exercised against you. Write them naked, but out of the money, if you must otherwise you're going to get killed.