Assuming question is about business class experience, then I would pick UA IAD-GVA over LX ORD-ZRH. I find the UA Polaris seats more comfortable than LX business seats. LX would have better food and probably better service, but I find LX overall average and similar to LH.

Also better transfer and lounge experience, IAD Polaris lounge vs ORD T5 LX lounge. Although ZRH lounge is nicer than GVA.

No comment on the timing and schedule since everyone has different priorities.