If your opponent's best players are guards but they do not shoot many 3 point shots (< 20% 3 point attempts) does playing a + defense give any additional advantage versus guards other than versus the 3 point shots? Thanks

If I see a opponent who's top 3 or 4 scorers are all guards, but they don't shoot many 3's, I'll usually go -1, 0, or +1 depending on what percentage of the scoring they do. The only way those types of guards can score efficiently is to get to the FT line so avoiding a heavily negative defense can help take that away. It can vary by the type of defensive set that you're running though. With FCP, I'd be more inclined to go 0, +1, or even +2.