Yes smart farm seems really fast. Put it on 10 10 and use bigger troops like giant and wizards.
You're not missing a setting. While you can bot 24/7, if you don't need to then don't. Just my opinion based on botting in multiple types of games. 8 hrs or less a day is usually really safe. 8-16 hrs is a little riskier. Over 16 hrs is asking for trouble.
I stay around the 15ish hr a day range and have the bot log out after each attack. Build a crows base and there's a low chance you'll be attacked when logged out. That is if you stay in gold/crystal range. I get attacked maybe once every 24 hrs even without a shield and logging out after every attack.