If you've already got the verification process sorted out, then I think you're right - you don't need to do anything else. As far as I know, Germany is one of the Visa Waiver countries. But I don't know for certain - I'd definitely check that first, because if I'm wrong you'll need a Visa!
Having said that, bear this in mind: If you're hour-building, and not receiving any instruction, a Visa Waiver is all you need to enter the country. Now, how many immigration officials do you know who would know the difference between a check-out, a BFR, and "flight training"? And if the immigration officials decide not to let you in, you're not going in - you have no right to appeal.
So, if you've got time, I'd get a Visa even though it's not required. If you don't have time, I'd be very careful about volunteering information to immigration officials. Don't lie to them. Tell them you're there for a holiday (which is true - you're visiting for a flying holiday in much the same way as many people visit for a skiing holiday). If possible, leave all your flying gear at home in Germany, and buy whatever you can while you're there. I'm not suggesting that you do anything illegal here - I'm just telling you to cover your back in case the immigration officials are less up to speed with the law than you are.
Have fun!
FFF
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