Option Lake Cruise
If you have good weather and you would like to take a lake cruiser, you could get off the train in Spiez. From the Spiez train station, it is about a 10 minutes "sign-posted" walk down to the landing, from where you could take a boat to Interlaken West. There are also a few restaurants right at the landing, if you did not have lunch yet or would like to sit down for coffee. (You could use fast baggage today if you plan on the Lake Cruise so you don't have to carry all your luggage with you).