If you like the E39 platform, think Alpina. BMW did not make an E39 M5 touring, but Alpina gave it a good go. I used to own B10 V8S #12, a 4.8 litre 375bhp family wagon. This is a tuned M62, so lacks the twin intakes and double vanos of the M5, but shifted well all the same
It also came in 4.6...