The game is fantastic, I am at the very end of it but keep putting off beating it. At first, I did not care for the idea of having the babies constantly around, but their inclusion lends itself to some pretty clever and creative puzzles. The game is very charming and fun overall. I also highly recommend Superstar Saga for the GBA as both are quite similar.
If you enjoyed the Paper Mario series or Mario RPG than I can guarantee you will love this.
See this ancient thread for more thoughts on the topic.
http://www.sydlexia.com/forums/viewtopic.php?t=734