I wouldn’t add on to my house since I’m happy with what I have. I wouldn’t fly any class except coach since I think it’s a waste to spend so much money when I’m perfectly comfortable in coach. If I was forced to upgrade I’d try to trade with someone who doesn’t look comfortable in coach.
Given the choice I’d take the lump sum so I can give it to those people or organizations who need it more than I do sooner rather than later.