Another problem with the "free will" theodicy is that it rests on a double standard. No-one thinks it impedes free will problematically when humans -- e.g. the police -- prevent acts of intentional evil. Why would it be any worse for God to do the exact same thing?
To take another example, we think it would be wrong for Bob to fail to save the drowning child. So why is it okay for God to do nothing? Again, this seems a plain double standard.