If you don't currently have one, then don't spring for an expensive one. Find one at consignment or an umbrella. You should not need it on the ship, we didn't for a 14 month old. (Though when we delivered FE gifts we baby wore). We have a B2B planned in Feb and won't be taking it then either.
The only consideration is if you think you might need it in the ports if you plan on doing walking or shopping and if your son would get tired of that quick. Depending on the ports, you might need to consider a stroller with larger wheels that won't catch in cracks or uneven pavement.