While 4-8 weeks seems like a long period of time you are looking at decent size continent that probably couldn't be more diverse. It's kind of the same question that you get from Europeans traveling to the US. They often do the same thing where they either drive cross country (without much time to actually see and experience much) or criss cross from coast to coast to check of the stereotypical tourist attractions from their list.I understand what you mean but, i'm only 20 and will be 21 when I'll star the trip so I will have a looooot of time (I hope so haha) to do it again.. I'll try to choose maybe 10-15(max) places with my Girlfriend to have enough time enjoying it. And for the gear, I'll bring the 8-16 because of the unique perspective it can achieve,for landscapes I'll do some panos with the 24-70, and the 120-300 is a Huge lens I know, but considering the 24-70 as my second longuest focal, I can't not bring the 120-300 because if I miss some long shots, i'll be a little mad at myself
If that's what you want people have given you the list already. And I'm not saying that Paris and Zermatt aren't worth visiting. Quite to the contrary. Only I would stick to 2, maybe 3 places that really interest you and get to know them better and beyond recreating the pictures and mental images that you already find at your local travel agent or on "Rick Steve's Europe" show.
To me traveling has always been about learning how places tick and where they're coming from. And I personally have a thing for putting things into historical contexts to understand the world a bit better. The one time I did one of those "20 countries in 10 days" undertakings with two very good friends we actually followed the path of one of the crusades with the added bonus of one of the friends being quite the expert on this subject. Not that the local food, drink and girls were dismissed along the way...Those were the days...
And I would stick to the 50 and the 24-70 and leave the rest at home.