"Perfect" in and of itself is what is called an ideal. Ideals can never be achieved, and are merely concepts. Compare this to the word normal.....what is normal? If you look at it, normal isn't actually "normal" as the word normal is an ideal, most people are not considered "normal", we all have our quirks and things that make us different. Being Odd, weird, strange or just plain different is what gives people spice of life and makes us all unique and different from each other. It goes like this for characters as well. If a charcter tries to be the ideal character, they are boring. Flaws add something to them, mold them and help to understand who they are. Their Strengths also do too. What fun is it to have a character who is good at everything? How can it even be explained that they are good at everything? Flaws add to character almost if not more than strengths. Something a character is good at can simply explained by saying they are good at it.
There is something I like to do with almost every character of mine that I make for RPing. I like to give them 1 irrational fear, 1 thing they very much dislike, and 1 thing they love. Say Byron, he had a fear of public speaking, now what that ever really be used? Probably not, but it added to him and made him feel more real to me. He also really disliked Spiders, though he wasn't petrified by them. Even little things can add depth to a character and make them feel more real.
((Also, in pissing contests where people tend to argue over who would be the better PC in a fight rarely matter. What does it matter how strong you are? Power Levels as shown by Dragon Ball Z and a lot of other works in media are extremely pointless. We as people aren't measured by just how powerful we are, We are measured by our everything that makes us, well us. Personalities can make a character who should be powerful weaker than everybody else around them at least in certain moments. Like Death the Kid in Soul Eater, he is the son of the Reaper, but he has such a problem with his obsession of symmetry it hinders him greatly. [and sometimes even helps him as well.]. No character in my eyes is ever stronger than another strictly speaking. If Graterras would be D and D accurate, the players would never be able to beat the Death Knight they are fighting right now unless they got absurdly lucky. However, due to the way this type of RP works, while he is indeed dangerous, they actually have a chance. To defeat a more "powerful" foe one needs only good strategy, planning, and good old fashioned creativity. While no doubt most of the characters in Under the Hill are extremely powerful, it is mostly the fact they can't die that makes them powerful, all of you would be long dead by now if that wasn't the case,[if you haven't noticed, most of your powers costs are indeed mitigated by the fact that you respawn upon death. Therefore no matter what you can go all out, the only problem will be trying to find your friends again.] not to mention that you are all supporting each other as well, that makes your characters infinitely more powerful than if they worked alone.)
TL:DR, Characters aren't only strong because of their actual power, there are many things that make them strong other than that. It best be remembered to, since if you lose sight of that a character simply becomes a laundry list of powers you can use, rather than an actual character.