Well, even now it's still too early to decide on the championship but for the mid-season and the end of the season too I don't think there will be much change here as the only possible additions are Dortmund and Leipzig which every year they are always in the Champions League zone and join the competition.
Last season there were a few other clubs that could have been in the mix but for now dark horse clubs like Freiburg and Union are still underperforming so maybe they will be excluded now.
For VFB they had a great start to the season and we saw that they improved a lot this season but in the last few games we saw how they started to have problems so I would also rule them out.
It definitely too early to decide the champion, so many things have changed in this season just as if they substituted each other, take a look at union Berlin that finished last season in fourth position are now in last position when match is still in 11 game while VfB Stuttgart that were battling not to relegate are now sitting comfortably in third point living behind second runner-up of last season with two points interval and Leipzig in the fourth position have one point in between, VfB Stuttgart performance this season show how serious the want to make it to champion league next season.
Football is just so unpredictable these days; most low-level teams are now performing really well and beating those considered to be of greater quality than them. The Bundesliga has always been a thrilling competition to watch, despite the fact that the league title has always been shared by Bayern Munich and Borussia Dortmund, with Bayern Munich winning the majority of the time since the league's inception. However, due to how competitive the league is, the teams that hold the second to fourth positions are always rotating. I believe this season we will see new clubs that will make it to the top four and qualify for the champions league next season. If most of the smaller teams showing expertise in their games are consistent till next year, they will find themselves in the next season’s champions league.
A team like Bayern Liverkusen can no longer be seen as a small team now because from all angle this season,they have shown that they are capable of winning greater things.They have been so consistent from day one till now,and they are showing no sign of tiredness.Liverkusen to me are the most prefered team that will win the Bundesliga tittle this season because Alonso is one of the best coach in Europe for now,and what he has done so far is not what one will feel he isn't serious for the Tittle.I think Dortmund and Bayern Munich are still there to compete but with what we've seen from Liverkusen so far,u can say they are the favourite for the tittle this time around.