Consider that the more damaged or diseased our brains become, the less we can think, remember or perceive. What then happens when our brains are completely dead? Do we quit thinking altogether? What are the implications for the afterlife? Do we receive new more perfect brains of a sort? How will that affect our personality and sense of identity? Will we truly be “ourselves”. I suppose that is something to ponder with the imperfect brains we currently possess.
We need to remember how what Christ has already done transforms who we are right now -- not later, once we get it together but right now in all the messes we've made.