Checkout ShareX, I was a long time Greenshot user (and it even integrates the nice annotation stuff from Greenshot) but I switched because it has an even nicer UI and a host of additional features while remaining simple to use (still free though.)
But ShareX does not have an image editor, like Greenshot. Which is the whole reason we are discussing alternatives to paint. Or am I wrong and someone implemented one?
It definitely has Greenshot's image editor baked right in.