So as the title says I think Stevens has done a very nice job building up the backup wing/forward depth with a combination of size, offball movement, and a variety of skill sets for Joe Mazzulla to choose from.
-Sam Hauser and Svi Mykhailiuk are both movement shooters that are better defensively than most think(I'd say Hauser is a bit better as both a shooter and a defender, but Svi adds some secondary playmaking which could be useful for 4 bench player lineups since Brogdon is more SG than PG).
-Oshae Brissett's 3 ball is questionable, but for a team that will(sadly) be playing a lot of games without all 3 of Porzingis, Rob and Horford available he's a useful PF to have as a guy who has the strength to body up opposing bigs similar to what Grant would sometimes do.
-Lamar Stevens and Jordan Walsh are both absolute dawgs on defense with great measurables that'll also bring a ton of grit and hustle for a team that lost a fair bit of it when Smart and Grant weren't brought back. If either of them can shoot it they'll be incredibly useful role players, but even if not the fact they play hard will still endear them to the fans and make them useful backup minute sponges for the regular season at least.
Another thing I love about all 5 of them is that they know how to move off the ball, either through well timed cuts or moving around the 3 point line to make themselves available as an easy kickout target. Even to more casual fans it was pretty obvious that as last season went on the offball movement oriented offense that Mazzulla had initially installed to start the year slowly faded away before essentially being non-existent by the time the playoffs had arrived. It seems pretty clear to me that Brad Stevens wants the team to be able to get back to that style of play as he's added guys not just with size, but also the ability and comfort to move off the ball which should really serve to benefit the offense in year 2 under Mazzulla.