Your question actually has a few different points, so here is what I think...
Point 1: We don't want to be answering the same question over and over again
The problem with this question is that the title doesn't really reflect the question. The question really isn't 'can I get a better translation for this' the question is actually 'is it possible to get better translations for idioms once they are translated from the Chinese'.
If it is just option 1, then this person needs to show more research effort and the question should be closed.
If it is option 2, then it is answered by user @fivecode, everyone here should now go and up vote his answer and then lets use this as an example next time someone asks for "a better translation" when one doesn't exist.
I refuse to believe that my Chinese/English skills are not good enough to answer this. Actually, everyone who has answered that question has provided the same answer and it is good enough. Don't look for magic when there isn't any. The magic is in the way it was created in the source language. "好好学习天天向上" If you study hard, you will get ahead. Want a better translation with some magic in it? You won't find one, even with a level 70 English Linguist Wizard Professor.
This person did ask the same question on the ELL site and got a similar answer, just with some big words thrown in.
Point 2: Idioms are unique to a language. Should such questions be allowed?
Yes, they should be allowed. We shouldn't shy away from anything that is on topic. We want people to approach us with idioms. But, they should be provided to us in the same way as any question on this site. They need to be worthwhile to answer and they need to show some effort.
The example question is weak and weak questions provide week answers and get low votes.
There are two reasons the example question is weak. 1) "读书好 好读书 读好书" is easy to translate, but the translation is boring. 2) People are not sure what this person really wants when everyone can clearly see what it says.
Point 3: Should we allow questions requesting English as the answer?
This has been asked by myself twice on our meta site and both times the answers have been Yes and with several upvotes.
We should have a better understanding of what the "magic" is inside the Chinese text, better than any English site. I personally received a High Distinction (above 90%) when I completed my 'The Chinese Classic Novel' class in university which required me to provide accurate translation of passages of text from the 四大名著. I have seen plenty of average (read crap) translations provided by professional translators and even lived with one for 2 years, I am willing to throw down the gauntlet to anyone with only skill in English to provide a better translation for these types of questions.
So how do we deal with this type of question and prevent a long tail of crap?
I personally have a very soft approach to moderation, because the community as a whole should be the moderators. Only one person has down-voted this question and nobody has voted to close.
However, we can make a stand. We can comment to the asker, to get them to show some effort and then either close it because it is too easy to answer and not a wortwhile question or we could upvote @fivecode's answer and then close all future questions of this type ("where is the magic in this idiom when there is none" type questions) with a reference pointing back to this question.
Lastly, we could just ignore it by not upvoting the question or the answers and leaving it as part of the long tail which is what is happening now.
We do have the tools to make the place better, but YES this type of question is on topic and YES we do have the skills to answer well thought, well researched, good quality questions which are similar.