I had a great boss several years ago, he gave us a fixed bonus to start at christmas and doubled it every year. As employees we'd already survived the cull rate and proven our worth - he was with the crew on every job and promoted a strong drive to knock it out and keep moving. my bonus if I had stayed with him ten years would have been 40,000. I believe he would have kept his word too.
I would have been happy knowing I would get $600 every year (Kicking myself for not staying but at the time I found him overstepping and trying to manage our personal lives too including telling me that my wife was holding me back in my work life the damn shame is I quit but he was right)
I'd say don't play favorites, issue a fair bonus if any, and put a "bonus gripe department" sign on a shop door that leads to the alley
a bonus is a gift -performance based- but a gift. never let them forget that.
