Welcome to FT and the oneworld forum.

My recommendation is that you credit your miles to AAdvantage, and sign up for the Platinum Challenge (see the sticky thread at the top of the AA forum). You will complete the challenge with the first return trip to Europe from LAX, and enjoy both Platinum status and 100% bonus for all miles earned while you hold the status.

As for getting op upgrades while you are PLT, well, it happens, but it is very rare, so don't count on it. What you will be able to do is to upgrade some of your domestic segments with the 500-mile electronic upgrades you will earn as you fly (the sticky has full details).