Paper Mario is one of my favorite games ever, and my favorite in the series. The other two just didn't have the same feel, especially Super Paper Mario, for obvious reasons. =P The storyline, events, characters, and overall feel and flow of the game were awesome. ^^
Yeah, I have to agree that the final boss was pretty easy, especially if you used the triple dip badge with offensive items and spent a bit of time leveling up to the maximum level. There were other bosses that added more challenge, I think. XP