MaxMind can be a great asset to your arsenal of anti-fraud weapons, if used correctly. Settings will vary depending on the business and their needs, of course. However, I do recommend you use phone verification at all times and also set a strict value for your MaxMind score.
There will always be legitimate orders getting caught as fraud, that is why you should always do a follow-up call or email to every client that signs up with you so you can verify the order manually and also give your clients a warm welcome. Your clients will not look down on you for this, they will actually appreciate it and will see that you're professional and that you care for them.