Hi Anneit,
Yes, it can be quite overwhelming when you start planning. I have spent endless (fun!) hours poring over websites, endless maps, blogs, etc. I first did a 12 day hiking trip in 2019, then again in 2022, and am going back in 2023. A part of my heart lies in those beautiful mountains of the Bernese Oberland region!
From Mürren, a wonderful hike is up to the Rotstock hut, along which you have the stunning views of the Eiger, Mönch and Jungfrau. The trail is generally quite easy, except for one short steep climb. It actually does not take more than approximately 3 hrs to get to the hut, which is very quaint and rustic! From there, you can continue hiking all the way up to the Sefinenfurgee pass. This trail becomes increasingly steeper, but the views are breathtaking. Last year we went to the top of the pass, and then turned back down because we were sleeping at the Rotstock hut. However, from the top of the Sefinenfurgee pass, one can continue towards the west, to the Gspalthorn hut. The Gspalthorn hut is also fantastic. I hiked to it last year from the village of Griesalp (which lies in the Kiental valley). This is also a spectacular hike!
I believe that many hikers go from the Gspalthorn hut to the Bluemlisalp hut. I will be going to the Bluemlisalp hut on my upcoming trip this summer, hiking up from Griesalp.
On my first trip in 2019 we went to the Lobhorn Hut, which lies at only 1900m. It is an easy trail from Sulwald, after taking a quaint short gondola ride from Isenfluh. It was a great experience and we met some wonderful locals at the hut (I am from Canada, but speak German).
Another fabulous hike with majestic views, is up to the Oberhornsee. From Stechelberg or Gimmelwald (not to be confused with Grindelwald), this hike takes approximately 8 hrs. A portion of it is quite difficult as you have a fairly steep steady uphill climb for approximately an hour. Once you slowly come out from the forest, the rewards are waiting for you, as the views are breathtaking. You will eventually come across a charming place , the Obersteinberg Inn. It is a family run place with cows and chickens nearby. You can have a bite to eat (cash only), with stunning views as you sit at a small table. This place has a few rooms to rent, but is not part of the SAC (Swiss Alpine Club). There is limited electricity.
So I hope some of this information helps!
Monica