My wife and I selected the P&O Ventura as a first cruise as the round trip to Lisbon was only for 7 days and we felt we could put up with this whatever it was like. Before booking the cruise our main concerns were would there be endless queues as upwards of 3,000 passengers could be milling around. (3,400 on our trip). Embarkation at Southampton took about 40 mins from dropping the car. We arrived spot on our allocated time of 12.30pm and were surprised to see how busy the terminal was already - virtually standing room only. There were about 20 embarkation pass groups in front of us but as mentioned it took about 40 mins.
We had a balcony cabin on B deck amidships on the port side. One day we had 8 foot waves (moderate apparently) but very little movement in our cabin or indeed of the ship. When docked we rarely had the sunny-side so if you want to sit on your balcony in the sun I would recommend starboard for this schedule. Never had to wait more than a minute or so for a lift except when the theatre (900 people) turned out. Easy to get seat/lounger outside.
We opted for fixed, first sitting dining and the service and food choice was excellent in the Cinnamon restaurant. We shared a table for six and the other couples were of similar age (late fifties)and we got on together fine. One other main reason for opting for a cruise was that my wife had recently been diagnosed with Coeliacs (gluten intolerance). We normally take city breaks and the thought of asking for gluten free food in non-English speaking countries was a bit daunting. Every evening the head waiter brought the next day's menus to my wife (lunch and dinner) and helped her choose. Apparently we could have got the ordered meals anywhere on the ship the next day just by quoting our table number. In fact my wife was able to make her own choices from the extensive buffet in the Waterside restaurant. On a couple of occasions when returning from trips in port, we went for the afternoon tea and the staff were able to supply suitable cakes, biscuits and sandwiches almost immediately on request.
B 422 (deck 11) port side with balcony. I chose this position as being amidships and about in the middle of the decks so assumed least movement in bad weather. Also, almost equidistant from dining rooms and pool/sun decks. Cabin generally very quiet but minor rattling on night with force 7 wind. We asked for the double bed configuration which I think gave more usable room than having it as two singles. There was a shower, basin and WC in the bathroom and this was rather cramped but adequate. For the majority of the port time our balcony was in the shade.