Im even too lazy to check bookmakers quotes, but Im sure that Bayerns odds for the title this year have returned to ridiculous values like 1.05 again, although formally Bayern is not in first place now and there are many competitors nearby.
Yes, very close: 
Even Dortmund and Leipzig are ranked higher. Champions Leage is best Union can realistically achieve. But I wouldn't be surprised if Union can finish above Dortmund and / or Leipzig.
Heh, I often check this market, so I already know in advance what bookmakers offer
I agree about Bolrussia and Leipzig, but I would rather consider such a possibility, not because Union Berlin looks strong, but because any of these teams can suddenly give out a series of unsuccessful games and drop out of the fight on their own.By the way, it turns out that bookmakers believe that Union Berlin will most likely get a ticket to the Champions League at the end of the season. In fact, it will be a very big success for them.