When choosing the institute as a Phd candidate, what aspects should be considered? (In Germany) I have finished M.Sc. in Stuttgart, Germany (computational structural mechanics field) and planning to do Phd. Afterward, I would go to industry after Phd. 
So, I would like to have your opinions about what aspects should be considered when choosing the field (or institute). I know the top priority is my academical interest. But if there are two topics (or two fields) I equally am interested in, what speculation should be taken account? For example, in Germany, is the power of supervising professor in academia, so could the professor be one of the resources when I am looking for the job in the relevant field?
Of course, as you said, your academic interests are important. And your advisor is also important: there is (in all places I know) no academic training "how to supervise" whatsoever - there are extremly bad advisors and very good ones. If you know something about the prospective advisors, take this into account. 
Of course, some advisors are good for some students and bad for others. As you want to go to industry, it could be nice not to have one of the "industry is evil"-type of advisors (if they are common or not is field-dependent). 

Having a good advisors is really important, especially in Germany the situation is really hierarchical and if your advisor is mean to you, you cannot efficiently complain about them.

Otherwise, pick a place where you can imagine to live in. And, it goes without saying, if you have a partner (and/or kids, or family you have to take care of) take their opinions absolutely into account! Having a good PhD position but a bad private life happens unfortunately very often to academics.