A number of factors, including money, factor in to the choice of opponent in an exhibition game. First, the NCAA has placed limitations on the opponents who can be scheduled. The Lady Vols used to schedule travel teams, who generally consisted of former D-1 players, until the NCAA outlawed them. So now you generally see Div II teams as exhibition opponents. Second, from an economic standpoint, you're going to look for a team in your general area so that the travel expenses are kept to a minimum. If you happen to have a top level D-II team in your area, so much the better. Otherwise you get the best you can get.
As to some differences over a practice with the male practice players, one difference is the actual game conditions, including referees and fans, that you just can't get in practice! I'd be willing to bet that the majority of coaches would tell you that, given the opportunity, they would rather have an exhibition game than not.
As to the 3- point shooting, the Lady Vols just had a cold night. In the game against Carson-Newman, they shot 40% from the three. And that is a good team percentage.
Jim