That's the battle of the employed world. Your happiness is important (rightly so) to you. It's also something that I, as a hiring manager, would not really factor in. For the functionality of my team, I need employees who can stick for a while and sustain long term projects. Moving around a bunch communicates (right or wrong) that you do not have the capability to help us with multi-year funding efforts, etc.

But I get the pursuit of being happy. Most jobs are sad places.