Creds: I'm an 18-time cruiser, wife a 25-time cruiser, but our first on Princess. My first time flying to Europe to catch a boat; she did it once before.
Complications for us, that relate to the cruise: Both retired, we figured it'd be dumb to fly over, cruise, fly right back. So, we self-planned a few days in London after our direct flight from Tampa; a "buffer"/safety night in Copenhagen before embarkation. At the other end, we did another half-day in Copenhagen before flying to Amsterdam, then training across the north coast (Ghent, Belgium was a magical, surprise revelation) to Paris for a few days before Chunneling back to London for our return flight.
For the cruise, that meant that we were expecting travel stress (hotel-changing, train/air schedule worries, BA pilots' strike worries) with the 11-day cruise in the middle of it all to be our respite from stress. It pretty much did exactly that. Like all cruises, it was nice not to have to pack up every few days and move on. Regal Princess provided our comfortable moving hotel through the Baltic.
Changed down two decks from our original mini-suite cabin. Found out that the skydeck walkers could peer into your cabin. This cabin was perfect! Being under the skydeck meant that our line of 8 or so cabins had a designed bulge outwards to mirror the skydeck. That meant that we had a larger than normal deck space for our class of cabin. Being on the bow end of the group gave us the most square footage of all.
General cabin size for a mini was great. My wife would be happy with a basic balcony cabin to save some (irrelevant to me) dollars. This was just enough larger to say "comforable!" Full-size couch (sleeper maybe?), long desk vanity opposite. A LOT of storage. I really liked the handy shelf going out the door (sunglasses, whatever)
Bathroom was good-sized. Would like two sinks, but it was okay.