Aren't we missing something here?
Respectfully, if your primary concern is International upgrades, forget UA or US... go to OneWorld.
AA issues 8 upgrades at 100k, and they're eligible in any fare class. The OW Alliance includes Cathay Pacific and Qantas for your Asia travels.
I'm a UA guy, but if my primary issue was overseas upgrades, especially with travel to/from Australia and Asia, I'd jump out of * and into OW.