The DoF is in charge of recruitment. He should be judged on it.
A large section of our support has already judged him negatively, like yourself. I don't entirely disagree with you.
Another section of the support believes that the manager (GvB) has failed to get the most out of the new signings.
I lean towards the latter, but don't think you're wrong. In fact, both arguments can be true at the same time.
Colak is a case in point: by all accounts a good signing, but I still don't think we've gotten the best out of him. His conversion rate is superb, but we provide him with very few chances in a game.
I'm interested to see what a new manager gets out of them all.