Since no one has tried to do anything with this thread, I'll take a crack at it. I'm gonna take RobZilla's idea of making three categories for evaluating the character. I'll talk about each one and put it on a scale of 1-10 for the character. The categories are as followed:
Character: This included personality and accomplishments, whether it was shown or stated. Shown is better because sometimes what is said by characters isn't always true. For major characters include only big events (If this is done for early crew members, it could be long). Any character development is welcome for this as well.
Design: Different people will have an opinion of the design and that's fine, but score should also be based on if it's memorable, as well as if it fits with the character based on the above category.
Comparison: This one could be tricky. For this category, we compare the character to the rest of the One Piece verse. Do they fit the overall feel of the world, both through design and character. Do they represent, in some way, what the story or world is to you?
With this set up, I'll do a character analysis to give you a better idea how it should work. Each category will be done in the order shown above. The character I'll be doing is Franky, since he is my favorite character, and there is enough to work off of to get my point across.
Character
! In a crew that has some strange members, Franky is one, if not the strangest. This is mostly apparent after the time skip, where we have time to see him do stuff. Before the time skip, he could go into a centaur mode, and he could shoot his arms out. After the time skip, we see things such as nipple lights, being able to change hair, shooting lasers out of his mouth, randomly turning into a tank, and having his own mecha. Plus he's powered by cola. There's still a lot of story left so he has more antics he will be able to show off.
! While being an oddball, Franky has his soft and serious side. We had a nice moment in this current arc where he talks to Luffy after finding out Ace's fruit is up for grabs. Franky shows compassion and is serious with what he's saying, showing that Franky can be confided in despite his over the top character. We also see that he's pretty smart, and not just because he can build things. When attacking the factory, despite Franky being outnumbered, he stays his ground, because if he tries going in, he'll allow reinforcements to go after Ussop and the others. Despite what others think of what happened, this showed that Franky not only thinks about what is going on at the moment, but the consequences of what actions he could take.
! Franky was touched by the Straw Hats greatly, as we see by the end of the Water 7 arc. Franky was devastated by what happened to his Mentor Tom. We see Franky cursing his passion to make things, which Tom hits him for. At the beginning of the arc we see Franky cares less about making stuff and more about stealing and helping his family. While not a terrible person, he seems to not care about creating things or others work. Franky is ready to just destroy the Going Merry without considering Ussop's feelings. At the end of the arc Franky has learned from seeing the Going Merry rescuing it's owners. It moves him deeply that he finally builds his first ship in a long time (this can be a connection to Tom, as he's building a ship for the next Pirate King). This is more apparent when we see Franky go out of his way to make a Going Merry paddle boat, to keep the memories alive. Since that arc Franky has created a number of things, which he is proud of, not ashamed of. This is one of the most moving stories for me when I really look into it.
Design
! I'll come right out and say it, when a lot of people were disliking Franky's new Character design, I loved it right away. Even before he became one of my favorites, and then my favorite, the design was perfect. To me Franky is best known for his over the topness, which is shown most when he does his Super Pose. His current design fits that silliness to a T, big and outlandish with unnecessary things (nipple lights and being able to change hair). Both designs show he's silliness by only wearing a speedo and Hawaiian shirt. He also randomly turns into a tank for hilarity, look at Punk Hazard and my Avatar for reference. The design not only fits him but is memorable. Even if you don't like it, Franky stands out anywhere and can't be forgotten, whether for good or bad reasons.
Comparison
! To me Franky represents what One Piece really is, a imaginative world with surprises at every corner. The world always has a new strange thing to show, that makes readers happy, excited, or disgusted. Franky always shows something to be happy (mini Merry), excited (he's got a freaking mech), or disgusting (nipple light. I'm not hating but some of the reactions I read were funny). In the story you have serious moments, light-hearted moments, and WTF moments. Franky also has those moments, whether it's the talk with luffy, meeting Tom's brother, or random Rabbi Franky Tank (Look at avatar for reference). Franky also fits the various opinions of One Piece, the whole mileage may vary (pun fully intended). Some people love everything about Franky (like me), some people like some aspects of him, and others just don't like him at all (because they don't like fun). The same can be said about the series, people like all or a lot of it, there are many parts they don't like but still see the good of it, and those who don't like it period (for good or bad reasons). If I had to choose a character that represented everything about the series, to me that would be Franky.
So there is my reason's. I could go into more detail, but this gets the point across well enough I believe. Now I will give a scoring sheet about what each range includes. 1 point is the lowest you can give
3-6: Either a one off character, not much to say about them, or just a terrible character.
7-12: Not great, but has some redeeming qualities. If used more and given more depth, has the potential to be great.
13-20: Good. Won't be the most memorable, but won't be forgotten. This is really good for a one time character.
21-26: Very good. This character shows a lot and is liked very well. Score can increase or decrease in the future, but for now is a solid character
27-30: Super level of awesomeness. This character is memorable and has a lot going for it. Not only that, it truly represents what's good about One Piece.
Here is my break down for Franky.
Character: 9.5
Design: 9
Comparison: 10
Overall: 28.5
Franky is a top contender for one of the best characters of this Manga, especially when compared to straw hats. When he is shown, he always has something memorable to show. He is funny, smart, and serious when the situation calls for it. Overall he has a great range and he contributes a lot to the crew.
Let me know what you think, and if there are ways to improve this. I read some of this thread and it would be a shame for it to go to waste. I'm going to try 2 other characters to see if any interest sparks up. White Beard and this arcs seemingly favorite new character (He is mine) Bartolomeo.