I also have my alt account at a very similar level and someone stole 1 part from me 2x and I'm at a 3 Fort and 3 Faith. The same person who attacked you also attacked me and lost HAHAH that's what they get! I think a level 4 Fort will really keep it safe but it can get expensive adding up the parts to just stay safe. I don't even have my power up at all since this will solely be for farming.