While I been swinging on DuoLingo's Spanish tree branches for some time, I just recently ventured, somewhat gingerly, into the Immersion section. I am curious as to what the expectations are in regard to the quality and content of the translations. Should the goal be to adhere as closely as possible to the content and construction of the original article even if the piece is awkwardly written? For example, if the author's sentence is rambling and run on, should my translation do likewise or should I try to clean up the sentence? Another example: I translated a sentence that had mixed present and past tense verbs. While the sentence seemed somewhat awkward, I translated as best I could. Later, someone edited and change some of the present tense verbs to past tense. This translation did read better (and perhaps the problem was my lack of expertise) but clearly did not match the tense of some of the original verbs. I understand that there are many instances where a literal translation of the Spanish would not be the best English equivalent. How much leeway is there between maintaining the voice and intent of the original article and the creativity of the translator?
As an aside, I am somewhat disappointed by the inclusion of a down vote option, which seems counter to a positive learning experience. Better to just keep pushing for up votes, than knowing the rock I am shoving up the hill could roll back down.
There is a set of community guidelines for Immersion that you may find helpful. That said, not everyone will adhere to them, nor are they obliged to do so - strictly speaking. I find them reasonable though.
Natural rather than literal translation is to be preferred, but don't be surprised if you'r elegant use of an idiom in the target language gets reverted to a more literal one. It happens. Explain your reasoning if you revert it back again, and then move on. :)
For me maintaining the authors voice makes the most sense, it's their work after all. If it's awkward or downright awful, upload a better article instead! However, you're free to change the punctuation to conform with the rules of the target language, and you should absolutely do the same with the sentence structure as well.
You said it all: "...maintaining the authors voice makes the most sense, it's their work after all..."
This page has a pretty thorough explanation of our unofficial Immersion guidelines.
With Spanish in particular, you'll find a lot of sentences that would be run-ons if translated directly into English. Feel free to change these into two (or more) sentences to make it more grammatical in English, but try to keep the tone similar to the original when you translate. I try to leave an explanation whenever I do something creative like that, which helps avoid others switching the translation back to something more direct.