I really like my Miles & More status. If you look first level status card Frequent Traveller aka silver.
What I really like is that you have lounge access already if you fly with those Miles & More companies, like LH, OS, LX etc, here I do not mean parthers.
Of course this is excellent benefit when you are living Europe. Other excellent benefits are that miles do not expire and executive bonus which means that you get additional miles on certain airlines. And not to forget that card is valid for two years.
Main thing in my opinion is to compare and then to stick to one card per alliance.