You and I are sitting in the very same boat, Lady.
If it's any help, I plan on getting $150 of DL dining for August (during double miles for all charges of course) mainly through purchasing gift certs - one joint here is ok but only gives miles two days a week (Sun/Mon)
So, I'll buy a hundred bucks or so from them on one of those days, nab the miles and dine when I want to. ^
After I get fulfill the $150 for August, I doubt I'll go for more Delta miles. Instead, I'll start working on my Alaska and American promos.