You want some graveyard interactions for the long games or to stop things from looping, and this gives you a bonus every time you do
For example, the game has a Slowpoke card with its original Base Set artwork, and then a full-art variant that removes the frame to reveal lots of other Slowpoke crawling all over the card in humorous fashion
If you stick solely to Vampire Aristocrats like the precon promotes then I think Clavileno and Carmen are about the same power level where it boils down your own preferences and your own meta: Clavileno is cheaper and provides a slow but consistent payoff, whereas Carmen is more expensive but also more explosive and randomly becomes more powerful if you happen to play against decks that sacrifice a lot (fetchlands, treasures, other Aristocrats etc.)
Its one of the few archetypes outside of Heroes that was well supported during the GX era, arguably the second most popular version of the Yu-Gi-Oh anime
Goblin Sharpshooter works great in all sorts of decks, not just goblins