DMI stands for “deliberately meaningless index”. In an absolute best case scenario, it’s an incredibly rough approximation of quality of player that incorporates in some degree skill levels, stamina, game shape (all of which include sub-levels), and whether or not the player is receiving training each Friday. On average, looking at salary and game shape can be more worthwhile for both yours and your opponents’ players.
New players (such as the starred ones that you have been given for going through the tutorial, and draft picks once the draft happens to begin the new season in a couple weeks) will have a DMI of 0 until the first training update after they are received- and this further indicates the DMI is not worth using to evaluate those players.
Players’ wage/salary is a weekly pay-out, and is determined during off-season processing for the entirety of the new season (this will happen in the next couple weeks and should be outlined in the “S64-S64” thread in this help forum). The “best position” shown beside each player on your roster is the one in which his salary calculation will be the HIGHEST, but not necessarily always the best. The top six skills (Jump shot, range, outside def, handling, driving, and passing) all lead to valuations that are higher for guards, and the next four (inside shot, inside def, rebounding, blocking) are typically higher for centers and power forwards. As might be guessed, higher skills mean higher salary, and training a player all season will often result in a pretty hefty salary increase during the off-season.