Three levels to this...
Craft development...WE all know that in order to develop a craft you have to be able to be dogged, persistent, disciplined and faithful to the craft. The problem however with saying that that type of persoanlity is the best for is that some are more naturally gifted than others, so the specific personality skills that go into craft development may not be as important to some as they are to others.
Execution...one you have developed the craft...You have to be ale to find a way to execute, and execute under pressure...that may be an entirely dfferent animal than that needed for the development of the skills...and that may come in many personality forms...some play better as Type A's...some more cognitive. In individual sports the proof is in the execution, and from a personality standpoint there are a bunch of emotional and cognitive ways to make a skill set "sing".
..but the REAL wild card is that in order to succeed in any team sport you need to be able to convince the decision makers (those with the power) that you have the right personality. They have to believe in you and your mental skill set. The problem of coure is that is subjective rather than objective. Unless you are statistically so far over the bubble that you cannot be denied, then you are going to be caught up in the personal bias of those with the power to play, sit or promote you...in great part based upon wether they think you have the right personality type. That process includes those personality tests given at college camps and by MLB organizations.