Don't worry about missing out on lakefront Annecy, pretty as it is - in Interlaken you're situated between two lakes with public boats going up and down if you can spare the time.

And also from Interlaken I recommend going up on the Niesen because it is not a part of the Alps but of the "Voralpen" - the "frontrange" from where you have splendid views of the really high peaks, better views than once you're in amongst them: http://www.niesen.ch/en/funiculair/i...ular/?oid=1870

569 km might not be bad. Train travel in Switzerland is a joy. ;-)

I suppose you will do your Zurich -> Pfaffikon -> Rapperswil -> Wollerau -> Bern -> Murten -> Interlaken -> Wengen -> Lugano zig zagging by car, otherwwise you would waste much more time than the 30 minutes between your Como itinerary and Verzasca Valley.
You could easily include Gstaad by driving from Murten via Fribourg - motorway - Bulle - Chateau d'Oex - Gstaad - Zweisimmen to Interlaken (45 miles more).

I'm sure trains are awesome, but they are limiting too. More flexibility with a car, and I think way cheaper

I've driven all over Switzerland and it was fine -but if going largely to Alpine areas cars are awful - can't go above a certain point often and be parked at remote parking lots. Like at Zermatt - parking lots way out of town and shuttle train takes you in.

But cars are fine and can be thrilling say on Alpine Passes- but I've found side roads can be tedioulsy slow at times and motorways boring.