Since switching to a 3-4-3 they've actually been pretty good. I would look at the last week before the winter break as a little bit of an exception. 3 games in 6 days at the end of the year, the last 2 being againt Leipzig and Hoffenheim. And even in those they were the (far) better teams. Just unlucky and/or tired (especially against Hoffenheim).
Assuming they keep playing in a 3-4-3, Zorc has his work cut out for him in the winter. Bruun Larsen is not good enough to play. Götze has no position in a 3-4-3. Paco is not ideal up front. Dahoud will not be the player we hoped he could be. As it stands, only Sancho, Reus and Hazard are suitable for one of the 3 offensive positions. Maybe Gio Reyna can get a few minutes. But he's only 17 and I don't know how far along he is. Though he looks brilliant playing in the Youth League. Still, we'll need at least one winger. If we can get Haaland as well, great. But with Raiola as his agent I wouldn't hold my breath.
Favre won't be sacked during the break. Maybe if they have another bad streak during spring. But my bet is on him staying until summer. There is no obvious candidate for his position available at the moment. Summer may offer some more opportunities (Farke, Kohfeldt for example).
Our biggest problem in my opinion is that we have had no consistent philosophy since Tuchel. High intensity Peter Bosz, followed by low intensity, low block Peter Stöger and now Favre who focuses on low risk passes and a lot of patience in creating chances. This results in the roster problems I've listed above. There are a lot of questions for this season and especially next with possibly Piszczek, Hakimi, Sancho, Götze, Dahoud, Bruun Larsen all but guaranteed to leave and a few others also in question.