The ones you redeemed for are exceptional value and I agree entirely. The fact that you're holding 500K in excess of what you need for you current travel plans exposes you to devaluation. Miles are a promissory note for future travel, but with no guarantee you can use them.
- Avianca could devalue several times between now and then, making your valuation 1/4 of what you thought.
- Avianca could leave Star Alliance, and force you to use them only on Avianca metal.
- Etc
You've got nothing but a liability until you redeem them for travel.
Park Hyatts are nice, I have to say that the ones I've stayed in at Milan, Tokyo, Buenos Aires have been solid. Other properties are decent enough in a pinch if you are fancy.
I gamed a casino loyalty program, so they give me free things. It isn't something that is really replicable unless you know a ton about gambling, are willing to lose money, etc. Free MS means that I can now withdraw from $3K upwards per day on the cruise and it charges as Travel, earning 4.5 cents on the Altitude card, or 3x on the TYP card.
That is nice! My gambling days are pretty much over. Used to go often to play BJ with a group of bridge players when AC just opened up. Now I think I might make some mistakes and at this stage of life I'm not really willing to risk a lot. That's why I don't even play anymore: If I won or lost a few hundred, no matter and if I played at a $100 table I could lose more than I'm comfortable with.
I say it because if you were in the same boat today, minus that glut of points you may feel more inclined to earn more. The 500K lifemiles are a large cushion. But rather than deplete then buy again, might be worth the occasional card to keep things humming along.