It's too bad you're flying United First, but when it's 80K vs. 110K (Lufthansa on the same route), I don't blame you. If you do have the extra 30K miles x 2 and you don't mind splurging, I would move to Lufthansa on the way back for a true first class experience (keep UA business on the way out). Once you experience the First Class Terminal and LH onboard service, you'll thank me.

I wouldn't worry about a downgrade and I think 1A and 2A are good choices, but it certainly will be much easier to communicate if your companion was in 1C.

Enjoy it. Hopefully you get a nice crew.