Not really, “of existence” makes me itch. And a khandha is not an “aspect”.
I think the point is that it is not extraneous: it is what āyatana means in this context. In fact you could just drop “fields” and it works fine. The only reason for saying “fields” is to keep a connection with other uses of āyatana, but that is not really necessary. So a minimal translation would better be:
the manifestation of the aggregates, the acquisition of the senses.
The problem is that in English we have an ordinary word “senses” that covers pretty much the same meaning as āyatana, but we don’t have anything that means what khandha means in this case.
When the translator does their job of rendering the meaning into English, sometimes you might find it challenging because it conflicts with your personal interpretation. To which I say, you’re welcome.