Kindness is Underrated (2014)
As a developer, kindness is EARNED, you want people to be kind to you despite of who you are and your mediocre contribution to the code base , unnecessarily  refactoring code when you're meant to be working on an important feature ? No sir, I don't think it'll be kindness you will get from or any business manager.If however you want well deserved respect and kindness, show that you excel at your job, you are able to deliver for me in a timely fashion and exceeding expectation.
You can't handle being criticised ? You have no business being in business, go open a charity bookshop. 
One has to understand, developers like in any other creative industry can go off on a tangent by themselves if not  given direction explicitly, sometimes that means being very much assertive and firm.
If that is perceived as being unkind then tough luck.