The problem lies in Heaven being the pinnacle of perfection, the ultimate reward, so most authors and filmmakers end up feeling not quite up to the task of portraying it (not to mention, one person's heaven is another person's Hell). The easy way out is to use Fluffy Cloud Heaven, The Theme Park Version of Heaven. When that doesn't fit the theme of the setting, the solution is to not show it at all, save perhaps as a tunnel of light for the departed to enter. Or an escalator. An older version.