I do think you need to choose carefully when consider a voyage by freighter.
I did a trip on a container ship 4 years ago that was for 8 weeks but left after 3 weeks.
When I joined the ship I was left completely to my own devices which on its own wasn't so bad, but I had no information on the ports of call regarding getting ashore, and the ships crew were not able to help. I would have expected at the very minimum a compendium of some sort with things to see and do at each port and how to get there. It seemed once you were onboard no-one was interested in you.
When we arrived at the first port, myself and a fellow passenger had to wait at the gangway for about 40 minutes before a shuttle finally picked us up. No-one was interested in looking after passengers. Then we spent another 15 minutes being taken around the terminal before being dropped off at the gate. It was then another 30 minutes before we were able to get a taxi, and so timespent ashore was minimal.
At the second port, we just planned to wander around the confines of the port area because we didn't know what we could do, but fortunately a customs officer told us about a train station 20 minutes away, so we were able to catch that and go into the city. This reiterated my point that the ship did not provide any helpful information to the passengers.
When I left the ship, I was kept on board sitting face to face with immigration officials for 3 hours. They made all the passengers wait until they had seen the entire crew before handing us our passports and the passengers still on board wasted all that time.
The food on board was very ordinary, and for one meal I was served up tripe which was inedible. Sometimes I was sure that leftovers were used in the next days soups.
I also found out that at one of the ports we were going to, you couldn't go ashore at all. That was never mentioned beforehand.
The air conditioning didn't work all that well and one passenger had problems with her toilet. She asked several times to have it fixed without success. Out of desparation she asked the Chief Engineer while at dinner, and was promptly scolded for bringing this up at meal time.
There was also nowhere to go outside during the daytime, as container ships now have box like superstructures, and the decks, railings etc were very dirty so it was impossible to find a space to relax.
Maybe I was unlucky as obviously some passengers have had some excellent experiences, and it also depends on what you expect out of it. I admit that perhaps my expectations were a bit high, as I did a 2 month trip 30 years ago on Royal Interocean Lines Straat Cumberland, and loved every moment of it.
