Although you've got a ton of points/miles in your storehouse, I'd do a little more research on how you might be able to revive any points/miles that have lapsed. Might as well have as big a bundle to play with as you can, especially because you want to fly first class!

You're fortunate. You've got many options, especially since you have a good stash of Starpoints which may be redeemed with a number of partners and which provide access to some nice high-end resort properties in Europe. Even with the programs where you have relatively few miles, many will allow you to book one-way awards so you could fly BA one way and AA back (and lots of other combinations as well).

I'd be tempted to plan my trips around LH and *A partner awards while staying in SPG properties. Use your other airline programs (and supplement with Starpoint conversions) as necessary to meet any scheduling/destination needs.

All of us would be happy to have your type of questions!