One of the reasons that @midlet would be a great choice as a future dolphin is because he is a walking breathing billboard for Steemit. He took the time to assist me with learning much of the platform and gives great honest feedback when commenting on various blogs.
He is not just concerned with getting upvotes but also establishing quality relationships and sharing his technical expertise. He would certainly bring the diversity that you are looking for and is someone who understands how to build and retain the community.