Don't be like this mate because those Comments are constructive criticism and you must be thankful about their Insights in this matter , actually some of them are advising you in right manner  so better be thankful.

and also you can't blame them because this kind of service you offered are rare and only Few people have the Guts to offer this because this will really get more attention as what you are having now.

While i am not against your service yet i don't think it is appropriate for an account owner to Hire someone to post for him, if he has no time to be active in forum then let His account sleep for a while and come back and join campaigns when he has the time enough to fulfill His obligation in tasks and not from others that may cause him bad credit in future.

If you can make good posts, why not to join signature campaign yourself? Ok, I know that it takes some time to rank up, but for decent poster it's not that difficult task. And out of curiosity, how much you want to get for this work?
You had to start self-moderated topic if you don't want to hear negative comments about yourself.