This is a very nice city with parts of the "old town" right at the docks. Most of the really good places places of interest such as the Flobanen Funicular, Bryggen's Museum, Hanseatic Museum, The Fish Market and the Petroleum Museum are in easy walking distance. You might consider the hop on hop off service which takes you around a larger area. A Bergen Card which provides some discounted or free admissions can be purchased across from the Fish Market, but you may not have enough time to visit enough sites to make it worthwhile. A trip to Troldhaugen, the Stave Church or Grieg's home are excursions outside of Bergen that should be considered.
This port rates a 5 ONLY if you take an excursion that has a coach ride from Voss to Flam. We took the Flam Railway (very scenic but not as promoted) to Mydral, the Oslo/Bergen Railway (OK) from Mydral to Voss and a coach from Voss back to Flam. The coach ride was great and one of highlight of the entire cruise.