Please review my itinerary, thank you!

Hi bella2020, and welcome! I think you've definitely managed to arrange an impressive travel schedule. It may be a bit too tight on some days though. Some thoughts on your travel scheme:

Day 1: renting a car is an option or course, and I understand that it may come in handy when stayin in Beatenberg. Swiss public transport is great as well though. You could easily cover all travel plans using buses and trains.

Day 2: I'd personally prefer to visit the Jungfraujoch as early in the morning as possible. On most days, skies are clearer in the morning than in the afternoon. Moreover, the sun will be in a better position for making pictures (I'm not sure if this is important to you) towards the Aletsch glacier. However, it's best to adapt your scheme to weather circumstances of that day. Just check weather forecasts the evening before or the same morning, and then decide which order of plans is best.
With or without visiting the Jungfraujoch, I would advise to get down via Grindelwald. The Männlichen cable car offers great views of the Lauterbrunnen valley, and so does the cog railway down from Kleine Scheidegg and Wengen-Lauterbrunnen. Returning via Grindelwald allows you to explore another beautiful valley.

Day 3: Both Jungfraujoch and Schilthorn are great in their own ways, providing different views and experiences. If you like visiting mountain tops, and if weather is fine, just go for the Schilthorn as well. In all, this will be quite a full day. If it's a sunny day, you may want to skip the Trümmelbach falls (although they're quite impressive) and enjoy a relaxed afternoon or evening in Beatenberg.

Day 4: This is do-able, although it will be quite a long day as well.

Day 5: I'm not sure how much time you'd like to spend in both Lucerne and Mendrisio, but this may be too much for one day. Are you planning on staying in Mendrisio for the night, or do you have to move on to Italy the same day? Anyway, you'll have to drive to Lucerne first, which takes about 1h30. The trip from Lucerne to Mendrisio by car takes another 2h15/2h30. You may want to slow down a bit along the way and take some breaks, as the views are truly beautiful. If you leave early, it's all possible, and it's a matter of personal preference too. For example: you could spend your time in Lucerne from 9am to 12am, travel onto Mendrisio and do some shopping there between 3pm/4pm and 6 pm.

Yes, even with a car, the Swiss Half Fare Card will save you quite some money on the Jungfraujoch trip, other mountain trains and cable cars, and the boat ride.

Some bad weather alternatives are the Trümmelbach falls, the Aare gorge near Meiringen and the Beatus caves near Beatenberg. Further tips can be found on our Bernese Oberland day trip overview.

I hope this helps a bit!

Hello bella. You're right, Männlichen-Kleine Scheidegg can be preferred over Kleine Scheidegg-Männlichen because of the views. However, if you want to visit the Jungfraujoch first, you can just go for the Kleine Scheidegg-Männlichen variant. It's beautiful anyway; you should simply turn around a bit more often to take a look at the Eiger, Mönch and Jungfrau ;-). It would be too much of a hassle to get to Männlichen first after your Jungfraujoch visit, and then walk to Kleine Scheidegg. And if weather is fine all day long you could still choose to get up to the Männlichen first, take your hike, and then visit the Jungfraujoch. If the hiking trail is closed (which doesn't seem likely at the moment, as not that much snow has fallen over the past months), you could also hike down to Grindelwald from Alpiglen (a stop along the line Kleine Scheidegg-Grindelwald).

Another thing to consider, which just crossed my mind: I'm not sure when exactly you'll be visiting the region, but the Männlichen cable car is closed down for maintenance up to May 28. Alternatively, you could visit the Jungfraujoch getting up via Wengen and Kleine Scheidegg, return to Grindelwald and take the cable car to First from there (this one's open from May 21). That's a nice viewing point too, and you could take an easy hike to the Bachalpsee.

Meiringen is a lot closer to Brienz than Bern. The town itself is not that special, but you could visit the Reichenbach falls and/or the Aareschlucht, or get up to the Alpen Tower.