I wanted to add some baseball-inspired ideas (in honor of opening day) to TrueHoop's interesting project to help make basketball even better. Coined "Hoopidea," they've already had lots of good ideas about improving bad teams and bad defense.
My first idea is regarding blocked shots, similar to baseball's strikeout.
"If a defensive player can block an offensive player's shot so that it does not reach the rim, his team automatically receives possession."
Current situation: While crowd-pleasing, a blocked shot is not valued very much within the game itself. It seems most guards are instructed not to try too hard to block shots, lest they draw a foul. And when a center blocks a shot, the ball merely often goes back to the player who shot it, who now gets a second chance as the center is landing. It would be, as if, a pitcher who strikes out a batter then also had to run home, grab the baseball, and throw the batter out at first for it to count as an out.
Improved situation: This gives defenders an incentive to go for ball on tight last-second plays instead of always holding back to avoid a foul. It also makes a shot-blocker much more vital to his team than before, and increases showy collisions in the paint. It makes it less valuable for, say, a Tyler Hansbrough to throw up a wild shot in the lane in hopes of getting fouled or drawing a charge.
My second idea is regarding fast-break points.
If a team can score before the other team has any players within the circle (or within the key), the basket should be worth three points.
Current situation: Despite the number of great guards in the league, we still fail to see many up-tempo teams. Running teams have had a rather tough twenty years since the Showtime Lakers. During playoffs, teams get more cautious and less likely to run. Thus we get treated to slow playoff basketball with few incentives to run or make more risky passes. Also, steals are less valuable because often a team will hold the ball rather than break for the basket. Basically, a basketball "home run" where the offense makes a hit that none of the defenders can touch should be worth more than a single.
Improved situation: The emphasis on scoring quickly helps balance out the slow-it-down offense so that teams are more willing to play hurry-up on some possessions. Deeper teams, able to run more, are also rewarded with this method. This also can make late-game possessions a little more interesting. A breakaway steal and dunk is now worth 3, not 2, so it's more rewarding to press and gamble rather than lie back in a zone.