I totally understand the difficulties of finding good, comfy clothes to play live. If you are looking for a Rev vibe, grab some surplus camo pants and cut them into shorts, grab a black t-shirt that fits, and wear some soccer or running shoes. I've worn this on stage and it is light, comfortable, and fits the look of a metal band. In another group that plays mid-tempo rock I wear some nice jeans, dressy shoes, and a button-up black shirt. You can rock the Aronoff look and wear jeans and a black graphic t-shirt too.
When in doubt, ask the band how they want to look. It is important you are all on the same page image-wise. Regardless of what anyone else says, you are selling a product and packaging counts.