The NBA offseason has brought many changes to rosters, coaching staffs, and the list of championship contenders. As we draw closer to opening night, it’s time to move our focus from the potential impact of each offseason event and onto the broader issues that figure to define this season. The BDL 25 takes stock of, uh, 25 key storylines to get you up to speed on where the most fascinating teams, players, and people stand on the brink of 2016-17.

There is no reason for the Toronto Raptors to be pessimistic after the greatest season in franchise history. Toronto finished 2015-16 with a number of team-firsts — a record 56 wins, a No. 2 seed in the playoffs, and an appearance in the Eastern Conference Finals. Toronto looked headed for a sweep at the hands of the Cleveland Cavaliers in that series, but wins in Games 3 and 4 allowed them to hit the offseason with their pride intact. Raptors fans were understandably thrilled about their team’s accomplishments, and there’s plenty of reason to think they can match them this season.

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Unfortunately, matching the previous season is usually a problem in a league as progress-focused as the NBA. While a team can get better without necessarily winning more games or making it any deeper into the postseason, another year in which the Raptors serve as the second-best team in the East and stay massive underdogs to the Cavs would look a lot like stagnation. If that does occur, the franchise will have to decide if it’s content to stay merely very good.

Of course, this all presupposes that the Raptors aren’t built to make a big improvement in 2016-17. In part, that’s because the roster looks very similar to the one that left the court in late May.

Playoff hero Bismack Biyombo left for the Orlando Magic in free agency and was replaced by potential starting power forward Jared Sullinger, a player with plenty of weaknesses to outweigh his strengths. Draft picks Jakob Poeltl and Pascal Siakam will add depth to the frontcourt, but they will require time to develop. The summer was a success if only because Toronto re-signed All-Star DeMar DeRozan with no drama, but the reinforcements are likely going to have to come from internal player development.

The possibility of such improvement is unclear. Star point guard Kyle Lowry is now 30 years old and looked exhausted at various points in the postseason, while big 2015 free-agent acquisition DeMarre Caroll played just 26 games last season and hit 30 himself this summer. DeRozan is probably a safe bet to stay at his current level, but he’s also improved considerably over the past few years and may well be set to plateau. Center Jonas Valanciunas is still just 24 and could be ready to become one of the best big men in the East, but that’s been the hope for several seasons now.

Unless someone comes out of nowhere, Toronto can probably only expect marginal steps forward. That’s unlikely to be enough to beat Cleveland in a seven-game series unless LeBron James ages rapidly or Kyrie Irving falls into a well.

Many teams would be thrilled to win 56 games and reach the conference finals two seasons in a row. Yet other contenders could emerge in the East, as well, and there’s no certainty that the Raptors will maintain their position even if their quality stays relatively the same. The NBA is a tough league to manage from year to year, and staying similar is often a death blow. There’s no clear evidence that last season was a one-off for Toronto, but recreating that success might not be enough to keep pace with the rest of the league.

Previously, on BDL 25:

Chris Bosh’s increasingly hazy career prospects

Kevin Durant sets about winning back our love

Stephen Curry’s search for an encore, and for invincibility lost

The NBA, social activism and a change we need to see in 2016-17

The Trail Blazers, and the promise and peril of ‘pretty good’

Will the Pistons ever get into gear?

Introducing the (maybe) thoroughly modern Grizzlies

Is the new-look Indiana Pacers core worth fearing?

It’s time for Anthony Davis to resume blowing our minds

How will the Warriors recover from a historic Finals collapse?

Counting on the Clippers to contend is insane, so call them crazy

The 76ers and the fascinating challenge of figuring it all out

On the final ‘couple of years’ of Dirk Nowitzki in the NBA

Can Jimmy Butler and ‘the three alphas’ coexist on the Bulls?

The Knicks make no sense, which makes all the sense in the world

LeBron, the Cavs, and writing sequels to storybook endings

Russell Westbrook is going to absolutely go nuts this year

The Spurs’ post-Duncan challenge of winning the West

The Lakers venture into the post-Kobe era

Expect the Utah Jazz to take a big leap forward

Al Horford, the Celtics and building from the NBA middle

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Eric Freeman is a writer for Ball Don’t Lie on Yahoo Sports. Have a tip? Email him at efreeman_ysports@yahoo.com or follow him on Twitter!

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