Subtle traveler:

Perhaps related to what you just said, during awake and dream experiences water has at sometimes meant, "spirit" or "spirit world" so riding on a ship can mean traveling within the world of spirit or a spiritual path. The "friends" part is obvious.  The song represents the spirit of adventure.

For me "riding a bicycle" can be a symbol for spiritually progressing in a positive direction, riding on a bus or train can represent traveling in the spirit world, going down a flight of steps or elevator represents not progressing, moving downwards, while going up represents progressing upwards.

If I am in a house or car,  such house or car can represent me, and the things within the car or house represent what is limiting me. There have been occasions where I was meditating, and suddenly I would experience myself in the back seat of my car, and the person who drove my car, the standout personality trait of that person represented what limited me. (I haven't experienced this car message in quite a while).

I understand what such symbolism means through some form of intuition, inner knowing.

I haven't thought in terms of metaphors. Have you read Tom Campbell?

Actually, I do think of analogies, which I suppose is the same thing as metaphors.