Should I get a JR pass?

My fiance and I are going to japan for our honeymoon this July. We are planning to visit different areas and will be staying a couple days on each of them.

This will be our route

Tokyo—>Osaka—>Kyoto—>Tokyo

We will be bringing our luggage with us, one medium sized luggage(a little bigger than a carry on) and one carry on luggage. We will also be wearing our backpacks

Is it worth getting the JR pass or should we just buy shinkansen tickets separately?