If you got into e-Rewards via a non-airline program, the BA Avios should show up as an additional redemption option (I got in via Delta, and got all the USA options when Delta ended participation) .
But if you've got a way of merging your Avios accounts and are a heavy survey person, you can get 3000 Iberia Avios every 30 days (largest redemption option there) compared to only 1000 BA Avios per 30 days.
Or fi you're really clipping along with the surveys and have all the USA redemption options, you could do one of each and get 4K Avios a month.