just go clipless. Changing pedals does change your fit because the cleat makes different pedals have a different stack so your seat height would change a little. Be very receptive to feelings when you use clipless for the first time, the LBS can only set them up so much so if something doesnt quite feel right its best to take it seriously and work out why before you cause a problem.

For road riding clipless pedals are far superior to standard pedals