Now that I have played a little bit more and seen what game tactics can do... here are my observations.
Defensive observations
1.) It's always good to gameplan for their highest scorers. Take into account how good your defensive tactics are against your opponent's best scorer(s). If you have somebody who is a very good defender against their best scorer, I have let it ride on Man to Man; single him out and let your defense go.
2.) If your overall defense is mediocre and they have 2 to 3 players scoring 15+ points a game, I would check shooting percentages for their highest scorers and gameplan for the best 2 out of the 3. Example... If your opponent has a SG and SF that both have high FG % and their C has a low FG % but all averaging close to the same amount of points per game, I would gameplan against the SG and SF with either a 3-2 or possibly even a 1-3-1 depending on the remaining inside players PPG and Rebounding. Always gameplan against their best players with your best players and if you don't have GREAT players to defend with, use tactics against their stronger players.
3.) Full Court Press isn't something that I would use unless everyone on your team is in Strong (or better) Game Shape. Full Court Press does seem to sap the players Game Shape a little faster than anything else. FCP will get you more steals at the expense of slightly higher shooting percentages from your opponent. If your opponent already has a low shooting % as a team, FCP is a good tactic even if your defense is questionable. Force them to shoot a lot; the reward is worth it with the turnovers you force. Also, if you're going to use FCP, I would suggest bumping your team's enthusiasm for the game. They will play even harder Full Court Press defense.
Just my observations... I am no expert... yet.