Here's my perspective on FF mileage redemptions. I don't look at CPM.

I know that I can afford pretty much any domestic ticket, and just buy them myself. I don't feel the need for domestic first -- even transcon to California I can put up with.

However, when traveling to Europe, we really do want to fly business class. But I don't want to pay thousands per ticket for business class. So we pretty much use our miles exclusively for that. It's a comfort thing, and a cost factor because of the cost of the Europe tickets.