Personally, I am pro Carrot but I acknowledge that there are strong arguments for both sides.
Arguments that support Carrot joining the crew
- Role/Position on the ship
- Potential to inherit Pedro's will
One of the biggest things for me that Carrot has going for her is her potential as Lookout. She fills the position so well that I am suspicious of a red herring.
I have seen a few theories that put forth compelling evidence for Carrot's potential as the ship's Lookout and from what I gathered, Seeing seems to be a potential theme with Carrot's character.
• Carrot would like to see the world
• Her name is "Carrot". Now this may not hold much weight as carrots are the most popular food that bunnies/rabbits are known for but carrots are also associated with good eyesight.
I'm not sure if I have read this somewhere so this may be something that other theories have mentioned but as someone who would like to see the world, what better way to see the world than a Lookout? Also, bunnies rest during the day and are most active at dawn and dusk which should be valuable for a Lookout. *Side note: Lol This is a stretch but since the Strawhats are the crew to bring forth the "Dawn", wouldn't it be symbolic for Carrot - a bunny - to be active?
Arguments that do no support Carrot joining the crew
- Lack of distinct features aside from those that come from being a bunny
- Potentially overlaps with Chopper
Robby put forth a really compelling argument in regards to Carrot's design. Chopper is a reindeer with distinct features; Franky is a cyborg with distinct features; Brook is a skeleton with distinct features; Jinbei is a Fishman with distinct features. Carrot doesn't have distinct features other than those that come from being a bunny.
This argument certainly holds weight however, I'm not sure of the amount of weight that we should assign to this argument when we consider the designs of the other female members and the fact that female designs aren't one of Oda's strengths. Nami and Robin are relatively similar to a majority of female characters in One Piece. If you remove Carrot's bunny features, she becomes just as distinct as Nami and Robin when compared to other female characters.
There are credible arguments for both sides and neither completely makes or breaks Carrot's chances. At this point, I don't think either stance should be considered unreasonable.