I think in a way BA has lost some interest in DBA anyways, rumors are flying that they might sell them.
To be precise, they were never a franchise, that's why you can't compare them e.g. to Comair. Their livery has always been more different, e.g. the black belly.
I think they should keep all tail designs, the Bavaria tail represents their MUC base, the pop art tail their strong Berlin presence, and the other two Germany in general.
Once you have tasted flight, you will forever walk the earth with your eyes turned skyward, for there you have been...