Bird,
I am not a happy camper. I spent considerable time and effort writing a post to "help" you with your requested feedback and was finished, was going to post (doing this on a kindle) and accidently hit the back arrow. POST GONE! So now as I was tired before I am even more so now, I am going to give you the short hand version and if you wish more info as to the whys I will give you that later.
Making some assumptions and suggestions. Also I don't remember (I really should after following the Brewers all this time) every players info.
Assuming 12 pitchers (Will explain reasons why I suggest that if you wish. You and I think alot alike so we probably don't need to talk about it. I have considered the posibilities of an 11 man pen but that can be too dangerous in the post season).
Assuming standard bench - 1 catcher, 2 IF, 2 OF. However the Brewers could be better served with a different combination. I don't have all the information.
Ok. Without as much explanation as the previous disappearing post.
Koch - out (Too many unknowns. Cannot have a dead roster slot in the championship series).
RodRod - out (Not reliable to be used as a fielder in a championship series. An error could lose the game and that and bad defense cannot be allowed to be a part of the plan). Your offense can win games, however as you know in the games that the offense does not come through, pitching and DEFENSE will. No weak links!
Bennett - start vs. L, bench vs. R.
Willemse - bench vs. L, start vs. R.
Vargas - bench utility
All very good to elite defenders.
Hope this helps. Feel free to use any or all of my suggestions. Also if you do not wish to use any of my ramblings just make sure you check in your shoes/boots before you put them on next time as I may or may not be responsible for the contents thereof.
Have a good night!
Palaaemon