Need help with itinerary and train travel for 8 day trip Murren Zermatt Zurich

Searching on SBB it seems like there are many options depending on what time we actually can get on the train and how many changes we want to make.

Yes, so you don't have to worry about rushing, since there is a train that will get you there leaving just about anytime you arrive at the airport train station. Get the 8-day pass if you like. It will cover all the main train travel plus 50 discounts on te Schilthornbahn above Muerren and the Gornergratbahn and lifts in Zermatt, as well as public transportation in Zurich and back to the airport.

When you do hikes will be dependent on the weather, so just play it by ear.

For ease I recommend the Swiss Travel Pass 8 day.
Here is everything that it covers:
https://www.myswissalps.com/swisstravelpass/validity

If possible I recommend subtracting a day in Zurich and adding it to Murren to get more out of your pass and more varied hiking opportunities. Also I would go to Luzern after leaving Zermatt. There are luggage lockers at the train station.

Thank you for quick responses. I would have liked to add a day to Murren but right now hotel is booked. Also we have been to Lucerne twice before but you are correct that it is a must see.
I will try to just go with the flow and trust that the connections will be easy as everyone has said. And also be flexible on hikes as it seems that there is no way to really go wrong.

We are leaving Thursday for Switzerland for one week. We have three nights Murren, Two nights Zermatt and Two nights in Zurich. We have been to Lucerne and Bern and Zurich on previous trips. We are aiming for nice hikes with views with some downtime but also fine with being active for most of the day. Tentatively we plan to arrive afternoon Murren and hopefully have energy to possibly do Allmenhubel hike. Then after breakfast next day head we would like to hike Mannlichen to Kleine Shindegg, also see some of Lauterbrunnen, maybe hike to falls, and is there time for a stop in Wengen? We would like to be back in Murren by 4 or 5 pm.
And last full day in Murren we were going to go to Schilthorn (brunch reservations at Pizza Gloria). Should we hike from Birg after lunch? Any other suggestions on how to spend the rest of the day? Hike to Gimmelwald? Thanks in advance for advice. On next day we travel to Zermatt for two nights. Is there something we should do before we travel to Zermatt? We will have our luggage.

Below is my recommendation. A side note, even though you have a reservation for brunch at Schilthorn, I still would be flexible on the order in which you do these activities. If for some reason Day 2 is looking way better weather wise than Day 3, I'd consider switching them. You don't want to go up to the Schilthorn and not be able to see anything. And the hiking from Murren would be nice to be able to actually see the views. Sometimes you'll find that Schilthorn is in the clouds but Mannlichen is clear or vice versa, so it's good to stay somewhat flexible. Check the webcams for each early in the morning before deciding and check the weather forecast.

Murren Day 1 - arrive afternoon, walk around Murren, walk down the paved path to Gimmelwald and explore the little farms (you can buy local products from their self service fridges), depending on time you can do appetizers/Schwarz Monch at the Pension Gimmelwald or the fixed menu dinner. Or go back up to Murren for dinner. We love Hotel Alpenblick Restaurant (lots of local meats and produce, their local mountain burger is great). If you're feeling lazy and don't feel like walking down to Gimmelwald, you can also take the cable car.

Murren Day 2 - Train to Wengen early in the morning, immediately cable up to Mannlichen, do the Panorama Walk to Kleine Scheidegg. Lunch in KS (plenty of options). Train KS to Wengen, explore for an hour. Train down to Lauterbrunnen. Walk a bit on the path. If you really want to do Trummelbach Falls you’ll want to bus there to save time to make your 4/5 pm time back in Murren. Also be prepared for quite a line to get up to the falls (you have to ride a special elevator thing). I personally would just wander about a bit to experience the valley. Or you can rent an e-bike in Lauterbrunnen (Imboden) and you can see a ton of the valley in an hour. To me that’s more enjoyable than waiting in a line with a bunch of people.

Murren Day 3 - Up to Schilthorn for brunch. On the way back down, 2 options. IF you have good hiking ability, you can hike Birg to Murren via Bryndlii (all downhill so bring hiking poles) OR if you’re a more easy/moderate hiking ability, ride the Schilthornbahn back down to Murren and then go to the Allmendhubel. Ride that up and do the North Face hike from Allmendhubel back to Murren.
Birg hike details — https://www.alltrails.com/trail/switzerland/bern/birg-bryndli-murren?u=i

Departure Day - If you didn’t have time on Day 2, you could store your luggage in Lauterbrunnen and rent an e-bike for a couple hours to bike the valley. This would ease your timeline on Day 2 and allow you a bit more time in Kleine Scheidegg and/or Wengen.

This sounds perfect. Am I missing out by skipping grimselwald? Seems like many people have been saying First is crowded and more touristy. Thank you so much for help.

Grindlewald First is fine to skip. Your itinerary is great!

Another vote for the exceptional meals served at the Hotel Alpenblick restaurant. Tom is an awesome chef, and Jeanette could not be more welcoming. Worth the stroll to the north end of Mürren.