I think the option of posting comments or something like that to people's boat is great, i don't know just something to cheer up the person that spent in the boat some long time (5 minutes) or maybe a rating system to it, something like interacting more with the boat.
The game need more improvment, once i finished the easy level i couldn't get back to the menu. The colors of the menu isn't that good, but i liked the song (even being annoying).