Union Berlin and Borussia Dortmund will be the most interesting matches while Bayern Munich and Freiburg are not very interesting because it will be easy to predict that Bayern Munich will lose again, while in Dortmund vs Union Berlin it will be more interesting because they have a very strong team and took first place at the top of the standings.
Freiburg was on the second position on the current bundesliga standing. Bayern is placed under freiburg. that proves that if freiburg has capability to win against bayern. I think that you are underestimating freiburg at this moment. This team is also very consistent. It can't win in the last match but freiburg never lose. It was getting draw as the worst result from against another team. that proves if freiburg's performance is also being very consistent at this moment compared with bayern. Freiburg can make the result from the match become draw.
Union will win against dortmund easily.