Most flights up to MKE are single class; either ER-145/CR-200's. In that case ask the GA for an exit row-they have more legroom. On weekdays, 2 flights in the afternoon are CR-7's which have 1st class seating and overall bigger cabin. It looks like according to your time schedule, you might be on one of those. If that is the case you might board at C's lower gates. If not and you have to go to F there is the shuttle bus from C9 to E3, which is across from F3. Generally the later the day, especially Friday, greater chance of delay.