I'm going to be completely honest to you. Those texts need not only a copywriter, but someone who can turn them into something that does not look as if they had been written either by a machine or by some guy from El Paso whose grand grandparents crossed the border a hundred years ago. In other words: I don't know who wrote them, but he/she doesn't speak Spanish at all.
Good news is I can help you with this. I can provide you with professional English-Spanish translations/re-writings. I have a long term experience writing, proofreading AND translating for some of the most prominent Spanish magazines. Last but not least, I’m a native Spaniard and fluent in English (C2), which I think it's almost mandatory in order to make your articles look like they have been actually written by someone who speaks Spanish.
PS: My apologies if I'm being too honest. It's not arrogance, it's just that (just like you) I hate to see how people publish those kind of texts with no corrections, no revisions at all.