Hi,
I’ve been tracking a similar flight as you but you seem much more flexible. Because of your flexibility in terms of airports and dates, I think you should be able to do better, though by how much I’m not sure. You should also consider looking at LAX (bigger hub for europe) and driving or flying a cheap airline like Southwest to LA.

We’re all kind of waiting to see if in the next week or two any sales are offered for Europe peak summer travel. If you are diligent about checking every day, you might catch a good sale. Also, in some cases roundtrip to the same city is not cheaper than a multi city. Strange but true, so play around with random combinations of cities (both here in us and over there in Europe) and you never know what might pop up. You’re really lucky to have flexbility!

You will almost certainly not save anything by flying out of LAX. SFO will be cheaper to some cities, LAX to others, but typically fares are not drastically different. Even if LAX were a couple of hundred bucks cheaper you’d lose that getting between the two.

This year is just so expensive I’m not sure what advice to give. The consistently lowest fares to Europe from SFO are to Dublin, Shannon, Madrid, and Barcelona, but once you tack on flights to your other destinations they might not save much if anything. There may or may not be summer sales around the corner, but with the recent volcano-related losses I’m doubting it more and more. That said, I’m not sure you’ll risk much by giving it a couple of weeks to see.