Best "lake "scenic trips

Greetings to the forum! I would like to use my swiss pass to cruise/sightsee on a lake or two.
I'm considering the following possibilities....but would like other options/opinions.My bases will be in Brig,Lugano,Lucerne.My aim is "scenic travel/route" as much as the destination.
1.Murten to Neuchatel[or vice versa]
2.Fluelen to Lucerne
3.lugano to Morcote or Lugano to Ponte Tresa or Lugano to Gandria...which one to choose???
Would appreciate info on other scenic cruises near to my bases . In relation to the Fluelen/lucerne route...is it all interesting/scenic,or would I be better to shorten the trip and complete journey into Lucerne by train?:-)

Thanks Annika....You are quite right re the Murten-Neuchatel boat.I am interested to walk around Murten[the walled city] as suggested in a forum "scenic" town option,and thought I could possibly do both,probably from Brig[train via Kandersteg one way] However,weather and time will make the decision for me.Don't fall off your chair....am also "looking" at the possibility of also doing one of the "Niederhorn"hikes the same day!! Again my plans could well come unstuck once I'm in Switzerland+post Tour Du Mont Blanc body condition!