If the percentage for 3 point shooting is to be raised to make it more realistic i think the amount of 3s attempted should be lowered. 
If we look at TheUnrepentantGunner statistics for season 5 we can see that he averaged 39 attemps per game. For the current NBA season the team with the most attempts pr game is the Knicks with 29, hitting 35.8% of those. 
Next is the Orlando Magic with 26 attemps per game hitting 40% followed by the Hawks with 21 attemps and 38%. 
This team in my division 
(41432) had an average in season 5 of 36.9 attempts per game. This season its 31 a game. 
This team in Norway div1 
(41394) has an average of 32 3s a game. 
Not evidence, but it suggests to me that the amount of 3s attempted by an run and gun team is a bit high. 
On the other hand, not one team in the NBA ((still current season) has below 12 attempts a game. This season i average 6.8. I suppose that is a good thing, considering i hit only 19.4 % of those. Boosted i might add by stellar shooting by my Center who has hit 40% of his 3s. Yep, he has hit 2/5. 
But still lower than Amar'e Stoudemire 60% 3s this season, he hit 3/5.