Two Weeks in Northern Italy....Add Switzerland?

There's nothing to not like in either itinerary. I like Switzerland so I do like the second itinerary. If it were me, I'd reduce a day from Varena and add to Lauterbrunnen. Or, Take the day from Varenna, stop a night in Luzern and then head to Lauterbrunnen. Or, add the day to Lauterbrunnen and on day 14, take the train to Luzern, spend the night and head to the airport from Luzern. (unless you have an early flight)

Hi. My suggestion is a slight variation on #2:
Day 1: Flight to Zurich
Day 2: Land in Zurich, travel to Lauterbrunnen area
Day 3: Lauterbrunnen area
Day 4: Lauterbrunnen area
Day 5: Travel to Lake Como (Varenna) Maybe add a day in Lauterbrunnen and change this to day 6?
Day 6: Varenna
Day 7: Varenna
Day 8: Varenna
Day 9: TRAIN to Bolzano / BUS to Dolomites (Ortisei). Base in Ortisei, but easy access to surrounding towns.
Day 10: Dolomites (Ortisei)
Day 11: Dolomites (Ortisei)
Day 12: Dolomites (Ortisei)
Day 13: Dolomites (Ortisei)
Day 14: Train to MILAN
Day 15: Flight home

Changes / rationale: Yes, as long as there, you should include Swiss mountains. Different experience than Dolomites. Fly into Zurich, out of Milan (use 'Multi City' when booking air). Hassle of a car outweighs advantages. Easy bus from Bolzano to Ortisei; once in Ortisei, easy free bus service to neighboring towns to access many lifts / hikes. Going to Cortina is extra hassle; not enough different to warrant. Bus / train back to Milan to fly home.
Enjoy!!

If you do include Switzerland, I would go somewhere other than Lauterbrunnen which we found dark, set low down in a valley. Look at Grindelwald, Murren or Wengen, all up in the mountains with gorgeous mountain views..

We stayed in the Lauterbrunnen valley and loved it. We also found lodging less expensive in Lauterbrunnen if that matters. That said, we also loved Murren, Wengen and Gimmelwald. Did not like Grindelwald at all, very touristy. You will likely get as many opinions on where to stay as there is forum members. My suggestion would be to read up on the area and pick the area that sounds best to you.

Yes sorry I didn't mean to say staying in Lauterbrunnen directly, just somewhere in that area (I hadn't researched the individual towns yet). Thanks for all the great replies so far!!