With Star Alliance, though based on availability, you could definitely utilize/combine any or all of United, Lufthansa, Singapore, and Thai, etc. airlines on that particular itinerary. However, since that routing involves travel from North America, to Europe, then Asia, a higher amount of miles will be needed (I'm thinking 140K). And focusing on Star Alliance, particularly SQ's F product, borrowing from your own statement, this premium product really has no comparison whatsoever. Good luck!