The more parties they need and the more 'diverse' this coalition is, the more trouble they will have. It seems that you will need to include wither the AfD or the left-wing populist Wagenknecht league, which will be a serious headache for the regime.

Hell, the current federal government consists of the Social Democrats, Greens and Liberals, and even they have been engaged in non-stop infighting - despite their differences in actual substance if not posturing being rather minor, at least in my opinion.