I realize that there was previously a discussion on whether questions of politeness are on topic. However, recently there have been some questions such as this one on replying to a favor, this on replying to "what's up", and this on reminding people to reply to email. To me, this is like asking the users of EL&U to write a quick paragraph or phrase for them. It could be considered helpful to future users, but they sometimes seem to ask for writing services.
For example, in this question, the OP gives two sentences and then says "I can't think of any other ways to say this". Despite his apparent effort, he is asking for users to come up with a phrase for him. This isn't a question of "correct my sentence", but it comes close.
Would these be considered on-topic "questions from those learning English" or does it venture too far into proofreading or something else off-topic?