pixel_player127759086 Yes, the crew needed for a destination always overrides the sailor contract itself. As already suggested, if needed, you can use outdated ships in addition by using Sailor Swift captains which will give your ship more crew for the travel. But usually this should be just a short time workaround since especially at the early levels captains are pretty expensive to get. However, when the game is in progress, you usually have captains with leftover charges from earlier levels with very few crew addition which aren't very good to use for everything else. Being a higher level player you usually will have enough income to buy all captains available for coins which appear in your tavern daily. You should never buy the useless XP captain Decard Sail though and better save your gems for outstanding ships than for captains.
Another important longtime strategy is to collect ships which are very good to transport sailors. We usually call them exploration ships. They are rare and often hard to identify since while having more crew, they usually have very few cargo instead, so when looking for good cargo ships, you usually wouldn't consider getting them.
The point is, buy both cargo and expedition ships. You will need the cargo ships most of the time, but whenever you need to transport lots of sailors, deactivate some of your cargo ships and activate your ships which have much crew. It is a good idea to keep old sailing ships in your account, at least those with 100 crew and more, so never put them into the pointless museum. When you reach multislot ships like the 2-slot steam ships at level 70, it can be very interesting to temporarily retire a 2-slot ship with e.g. 140 crew and to switch to 2 single slot sailing ships with e.g. 100 crew each instead, because this way you will be able to transport 200 instead of 140 sailors.
Sadly, there is only one real exploration ship available from the standard offers. It is the La Pensée which has 200 crew when fully upgraded. If you do not yet have her, get her. She will be useful for hundreds of levels. If you manage to continue the contractors until Thomas Cook, he will reward you with the sailing ship Resolution which is even interesting as a cargo ship, but also has 500 crew. You might take a while to upgrade her though since this is pretty expensive.
For more good exploration ships you will need to wait for one offered in an event. For example, there were exploration ships for the winners of the competitions in the Halloween and Regatta events, a free gift PF Seaport for everyone at the games birthday last November and whenever you have the rare opportunity to get a ship which can be upgraded with tokens for either crew or cargo like in the actual event, it can be an interesting option to construct a full crew exploration ship.