LH has LAX-FRA on the 747-8i loaded into the system for next year. That will be a top notch J product. It's not flying yet, but it's something to consider if DL remains that much more expensive. As an earlier poster mentioned, you are flying enough to maintain DM with DL and 1K with UA. Or if almost all of your travel is US-Europe, maybe get status with LH and DL.

What about partner airlines? AF/KL don't have the best product, but AZ now has a great seat on their LAX-FCO route.