I can find awards pretty easily using most award programs. Using DL miles for low level intl awards to SJO, and Asia on DL flights has been close to impossible. I used to get awards left and right, with nary a problem, but that's not the case these days.
Is DL the worst airline? No. For actual flying and staff, they're fine, for an American carrier. However, part of the whole reason I give loyalty to one FF program over another is the benefits that it can give me.
DL has very much underserved this need. I mean, really, a US-Asia in Biz class for more than a RTW in Biz award? And these were not cherry picked days, or 2 months in advance. These were for 9-11 months in advance. And I was quite flexible on dates, routings, etc.
Since I was NW Plat for quite a few years, I obviously miss the old days. Service on the plane was acceptable, but the awards, perks and customer service for elites were great.
I think I would have been much more willing to go along with DL if they had actually been honest about stuff. They snuck huge changes in the program into promotional emails. The reasons they gave for taking free changes away was pretty laughable.
And instead of "Best in Class" PR BS, maybe a "This is going to hurt a bit" would have been better. Taking away all the WP perks, and then giving them all back for Diamond also seemed hypocritical.
DL has had some good things, such as rollover miles, and it seems that most people are still getting upgraded at a decent percentage for domestic flights.