Thanks for the feedback.
The idea behind my translations was to use the closest terms found in modern idiomatic English, not to imply that the cosmology is identical.
In translation, we face these issues all the time. There is no one right or wrong way of doing it.
However it is important to define and follow a clear “translation project”, which in my case, was to translate specialized terms in such a way that a non-specialist, with no prior knowledge of Buddhism or Buddhist cosmology, could read the translations and get a reasonable idea what they were saying.
Words like “world-system” or “thousand-fold world” are not really English, they are only found in Buddhism, and I fear that someone unfamilar with Buddhism would simply not know what they meant.
I’ll have a think about the issues that you raise.