I think you’re changing locations too much in this short amount of time, no reason to go to Bern twice. You’re going to spend a valuable amount of time packing up, checking in, checking out, etc. You're also not giving yourself any buffer for unpredictable mountain weather. Just because you WANT to do something on a certain day, doesn't mean the weather is going to allow it. Having an extra buffer day can mean the difference between getting to do something you really want to do and not being able to do it at all. If it were me personally, I'd pick narrow down to either Bern & Murren or Murren & Luzern, but if you want to do all 3, recommend the following:
Wed: Land, train to Bern, check in, tour city, dinner
Thursday: Leisurely morning, travel to Murren mid day, check in, explore Murren
Friday: Walk from Murren to Gimmelwald, then take cable up to Schilthorn, Birg Thrill Walk, back to Murren - if you still have extra time, go up to Allmendhubel and you can do some additional hiking/walking around up there
Saturday: Murren > Wengen, Mannlichen, Panorama Hike from Männlichen to Kleine Scheidegg > Lauerbrunnen (option to walk around a bit and/or e-bike the valley or just go back up to Murren)
Sunday: Murren to Luzern, afternoon in Luzern
Monday: Train to Milan from Luzern
If you want to narrow down, to give yourself some more time to really enjoy the places you're going, as well as some buffer for weather in the mountains, do this:
Wed: Land, train to Bern, check in, tour city, dinner
Thursday: Leisurely morning, travel to Murren mid day, check in, explore Murren
Friday: Walk from Murren to Gimmelwald, then take cable up to Schilthorn, Birg Thrill Walk, back to Murren - if you still have extra time, go up to Allmendhubel and you can do some additional hiking/walking around up there
Saturday: Murren > Wengen, Mannlichen, Panorama Hike from Männlichen to Kleine Scheidegg > Lauerbrunnen (option to walk around a bit and/or e-bike the valley or just go back up to Murren)
Sunday: Buffer day in Murren for weather. If you've had perfect weather, there are PLENTY of options to add on to this day. North Face hike, boat cruise on Lake Brienz or Lake Thun (stop at castles along the way), Grindlewald, I could list dozens of options....
Monday: Train Murren to Milan
OR
Wed: Land, train to Murren, explore Murren
Thursday: Walk from Murren to Gimmelwald, then take cable up to Schilthorn, Birg Thrill Walk, back to Murren - if you still have extra time, go up to Allmendhubel and you can do some additional hiking/walking around up there
Friday: Murren > Wengen, Mannlichen, Panorama Hike from Männlichen to Kleine Scheidegg > Lauerbrunnen (option to walk around a bit and/or e-bike the valley or just go back up to Murren)
Saturday: Buffer day in Murren for weather. If you've had perfect weather, there are PLENTY of options to add on to this day. North Face hike, boat cruise on Lake Brienz or Lake Thun (stop at castles along the way), Grindlewald, I could list dozens of options....
Sunday: Murren > Luzern
Monday: Train Luzern to Milan