I would stay in Lausanne if your current job is safe and you are not miserable. A few years ago, I would have said go for it but now is not the time to rock the boat especially if you have a family.
A move is not cheap also especially when you have kids.
Also you have not been holding the current position for a long time. Jumping from one job to another never looks good on a resume.
It is also hard to beat the quality of life the lake Leman area has to offer.