granular language settings for "Translate page..."

[puppybytes]

The translate page function is immensely helpful, but it has a few large annoyances for me.
1. I'm bilingual, I can ask Firefox not to translate my mother tongue, but I can't stop it from translating TO my language. Users should be able to choose to which language the translation feature defaults.

2. A related point: translate page defaults to translate from English to my native language. I never want it to translate pages from English. I can find no way to turn that off, since the settings for translate page grey out that option. Why?