Hi. We came across a variant idea last night by accident. It was our first game of marklin although have played previous 2 editions loads. Anyway when sorting out the cards we clearly didnt get them all separated as during play instead of turning over a train card a route card appeared instead!
We thought this would be kind of fun - shuffling say 10 random route cards into the train deck and have them appear just like train cards. Selection rules like locos.