Even though I know I have German ancestors, I still have several that I did not know much about when it comes to parents and siblings. With some ancestors, I can make a guess as to naming patterns, but with others I cannot.
One thing that I have noticed with some of my German ancestors is that they had a middle name or more than one given name. I forget now where I read this, but this was supposedly typical of German immigrants to the United States and possibly in Germany. (My memory is failing me on this one.) And then, on top of that, they might either go by one of those names in other documents. Now, I realize this does not sound so bad, but on top of this, I discovered that I had ancestors who had three or more given names. And to make matters worse, one of those ancestors apparently was known by either one or two of his given names. (At least that is how it appears to me at the moment.) Of course, with this ancestor, he apparently stuck with using the last two of his given names, but his children apparently did not follow that custom. It appears that they just chose to go by their first given name. Again, this is only what I have noticed for the German ancestors that I have done some research on. It could be that this one family is an oddity, but I guess I should not rely too much on generalizations.
As for names, many of my German ancestors and their siblings appear to have names that were commonly used in Germany. Of course, some of those names I might find odd, but then, that is probably because I live in American culture and not German culture. And then, there are my German ancestors who came from the Russian Empire, of whom I cannot make too many generalizations only because I know more about their lives and families in the United States. As for odd given names of my German ancestors, I think I'll start with my Russian-German ancestors.
As you may remember, I wrote about Anton and Caroline, my German ancestors from the Russian Empire. Anton and Caroline, along with Anton's siblings that came to the U. S., had several children. Among the names that they chose in common with Anton's siblings' children were August, Emma, Anna, Bertha, John, and Arthur. Anton was the only one among his brothers that did not name a son after him (as far as I know). Out of the above names mentioned, the ones I find unusual are August, Anton and Arthur. August and Anton only seem unusual to me because I live in an area where those names are uncommon. I realize Arthur is not unusual name, but since this family came from the Russian Empire, it is not a name that I would expect people from that area to give to their child. (Of course, I should state that the children given this name were born in the United States, so this might be a case of the families wanting or trying to assimilate into the American culture.)
As for my other German ancestors, most of the names given to their children are names that I would expect to find in a German culture. Of course, I have not yet researched all of my German ancestors, so this situation could easily change.