We have done Princess, Celebrity, HAL, Cyrstal, Cunard, and we are booked on NCL for this coming April. Have cruised out of Rome, Venice, Istanbul, Athens and Barcelona in the Mediterranean. Barcelona and Athens are the easiest.
We have also done Northern Europe and the Baltics out of Dover.
All European trips are very port intensive.
We typically do port tours on our own, with a small child that probably would work best.