Something to note about LX F booked on 016 tickets: they’ve been known to deny F lounge access at ZRH/GVA even for paid tickets in LX F when it is booked through UA. Their reasoning is that they only offer the F lounge to F pax who booked directly through them. It’s a really dumb rule.
There are some workarounds like having a mobile BP, because the paper one will say the also UA flight number. But sometimes they look into it further to see who you booked through even when you scan the mobile BP. You could get lucky like I did when flying BOM-ZRH-JFK in LX F, I had the mobile BP ready but when I arrived at the lounge their systems were down, so the agent just looked at my mobile BP to confirm I was in F, and copied my details down. I was nervous that I would get kicked out when they realized (which has actually happened to some people believe it or not). But nothing of the sort happened and I enjoyed the lounge.
But to be honest, Swiss F service onboard is better then LH, and LH is also very good for the most part in F service wise. But it’s not worth all these issues to fly LX, so I would stick with LH if I was you.