It is sometimes appropriate to add "I look forward to hearing from you" at the end of a letter or other similar communication. I am looking for a phrase that says more "I am happy if you react to this letter in some way" rather than "please write back". (To be precise, I really mean "please come to Latin.SE".) What would be an idiomatic way to express this in classical Latin? The Roman letters from antiquity must have a phrase that has this effect, but I'm not familiar with any.
A direct translation might be something like Expecto mihi de te audire licere, "I await a chance to hear about you".