I'd prefer Swiss at any time. Usually a much friendlier crew than LH. Especially ground staff in MUC can be horribly arrogant and unwilling to help. Furthermore, 55 minutes is more than sufficient to make a connection in ZRH. I fly them a lot and my OSL flight usually gives me between 30 and 40 minutes to make a connection and so far I made over 90%: they may even wait for you if your delay isn't too big (they've done that for me several times). Just follow the signs and you'll be fine. Food is equally bad in both cabins. The only advantage is that Swiss will get you a tasty chocolate, where LH nowadays gets you something that resembles chocolate. Both LX and LH have a galley where drinks and snacks are available during the flight. And Weero: no, they don't serve them from the lavatories (fortunately).
Talking about lavatories: having the lavatories downstairs (at hold luggage container level) is indeed a typical LH 'perk' that you won't find on any other airline for what I know.

Hope this helps.