I don't believe in reperations, what I do believe is that Germany simply should not benefit from a situation it created only a few decades after (and for reasons similiar to those that are motivating it today).
The remedy won't be easy, but creating a situation by using illegal means and then trying to benefit from the fruits of the labor from those illegal means, is not proper.
Of course, it is not going to be easy. But it is also impossible to account for, too. That kind of renders the whole argument for undoing the past, aimless.
At most, they can build a memorial to each other's wrongs, and carry on. At worst, they can fight it off again. Like Europeans(and most likely, groups of every living being on earth) have always been accustomed to, and settle it once-and-for-all. Until another issue can be thought of, to seek vengeance for, that is.
You're arguing that Germans, many of whom were not involved in World War 2, should be proportionally less represented in the parliament, and Poland should be over-represented to compensate for those killed in World War 2.
So you're supporting taking from the descendants of the 'bad guys' and giving to the descendants of the 'good guys.'