In the past, there was an obvious gulf between the quality of the Bundesliga (with the exception of Bayern when they were so dominant) and the other top European leagues. This is now no longer the case and I think by keeping their star players within their own league, the Germans have rapidly caught up.

The Bundesliga is a fantastic product for many reasons. As you have touched upon, the unpredictability is a key factor. Also as mentioned by Varan, the winter break is a great idea. Add into that the financial prudence (Bundesliga teams out of all the European leagues tend to spend the lowest percentage of their income on player wages). Also, the fans are allowed to stand up and sing in certain areas or sit down and watch in others, providing a better matchday experience for all types of fans and thus, a more relaxed yet passionate atmosphere.

Why would the players want to leave when German football is getting it so right? Our money-driven corporate cash cow known as the Premier League should take note before the bubble completely bursts

About getting their players, its not going to be so simple now, Germany has 4 UCL spots now.

Why would they go to BPL, plus Germany has a significant break in winter as well, players are less likely to get burned in Bundesliga,
BPL is just silly in this regard.