Sorry I'm late to the party; this took a bit of time to put together.
Portland: 99.4 points per game (Pace = 86.6 possessions per game; League Avg = 91.7)
2 point field goals - 49.0% (2422/4939), right at the league average of 48.5% (2499/5149)
3 point field goals - 38.3% (596/1555), well above the league average of 36.7% (545/1486)
Total offensive rebs - 1060, well above the league average of 905
Offensive rebounds that resulted in scores: ~493 (League average: 415.4)
Turnover rate: .125 turnovers per possession (League average: .133)
Portland's story:
There are four offensive statistic contributing the offensive rating: effective FG%, Turnover%, Offensive Rebound%, FTs per FGA. Of those four, we are in the top 8 in 3 of them (eFG% - 8th, TOV% - 7th, OReb% - 1st), and 17th in FTs per FGA.
The high offensive rebound count contributed to the slow pace (since offensive rebounds continue a single possession), and low turnover rate, while the high 3pt percentage and average 2pt percentage allowed Portland to have an average scoring year (99.4 vs 100.0 league average).
How does Portand improve?
1. Keep the offensive rebounding high; you can't for a second consider a high OReb% a bad thing.
2. Increase the pace by running a little more. Adding four more possessions a game would increase scoring by 2 or 3 points. It may be tough to increase pace on paper with the OReb% as high as it is.
3. Increase FT per FGA. More slashing (Andre Miller, anyone?) means more 2pt FGs which is where the FTs come from. This is a cheap way of increasing scoring.
4. Go away from the 3pt shot. The percentage was good, but the number of attempts belies a crutch in the system. This is why Andre Miller is just fine; he'll increase FTs by slashing, and passing to the post.
For a lark, here's Phoenix's stats. They had the 2nd best ORtg:
Phoenix: 109.4 points per game (Pace = 96.0 possessions per game; League Avg = 91.7)
2 point field goals - 53.7% (2820/5250), blowing away the league average of 48.5% (2499/5149)
3 points field goals - 38.3% (553/1445), well above the league average of 36.7% (545/1486)
Total offensive rebs - 900, right around the league average of 905
Offensive rebounds that resulted in scores: ~454 (League average: 415.4)
Turnover rate: .144 turnovers per possession (League average: .133)
Their story is almost the opposite of ours: a high-turnover gets a high ofensive rating with a high pace and blistering 2pt fg%. The low OReb is a result of the high FG%. If they lowered their turnover percentage, they'd be insanely efficient.