Interesting post...and I have a few points I'd like to add for context purposes.
Schalke got destroyed by the best team in the world, who appear to be better than they were last year.
Gladbach lost to the second best team in Germany, and played well, but just didn't have enough.
Werder lost to a club that suffers from massive identity issues. Something Hertha are the club that appears to try and bring up youth and play the long game, then the next week they will get the itch, and spend money that would leave you to believe they should be a top 3-4 team in Germany.
The point is, I did peg either Schalke, Gladbach, or Werder to go down, and I still don't think they will.
If Werder can not lose any players before the close of the transfer window, and especially keep hold of Rashica, I do think they will remain in the Bundesliga. I didn't watch the Bremen match, but I will watch the replay either today or tomorrow, but if what @Devil-Dick Willie and @nudge are saying is correct about the formation and tactics, then I can only hope that this is an issue that Bremen can recover from.
I do the think future of Bremen, sadly, rests on the hopes of other teams performing worse over the course of the year. I'm still not sold on Freiburg this year after all they have lost (although they do appear to have done a good job in replacing their losses), Stuttgart, Koln, Mainz, Arminia, and sadly even Augsburg are no way out of this conversation.
I still think Bremen have too much talent to go down, and I hope that they do get a result against Schalke this weekend to bring the hopes of some of their fans just a little bit.
Schalke were beaten by a scoreline that was misleading to me, as they didn't seem to give a shit after the 4th or 5th goal, which is sad to see, but it's likely that this won't even be Bayern's biggest win of the year with the team they have assembled.
Bremen will stay up, not comfortably, but I do think they stay up this year. Would be an absolutely tragedy if they were to get relegated this year.