The Allen comparison bums out people here, but I'm not the first to have made it. I think it was Bill Simmons and Zach Lowe. Allen was never a shooter, but he showed some ability to attack and finish at the rim early in his career. I really have to hope Smart ends up better than Tony Allen in Allen's prime. People have pointed out Smart's mediocre three point shooting as a sign of him being a superior offensive player. Allen was a terrible three point shooter. In 2007, Allen's per-36 numbers were 17 points, 5.5 rebounds, 2.5 assists, 2.2 steals with 51%/24%/78% shooting. He could score a little.
Personally, the Allen comparison bums me out simply because I think it's a really poor comparison.
I think it's like comparing Rajon Rondo to Chris Paul, based purely on the facts that both are a similar height and both are great passers.
Or like comparing Marc Gasol to Tyson Chandler because they are both a similar height and both are excellent defenders.
It's irrational.
Tony Allen and Marcus Smart have absolutely nothing at all in common other than the fact that both are around 6'4" and both are exceptional defensive players. As soon as you step beyond those two factors, they are completely different players in every single respect.
As you said Tony Allen could score - that's true. As you hinted, all of his offense came at the basket off drives, cuts, dunks or layups. That's completely different to Marcus Smart, who got the vast majority of his points off three point shots.
Allen couldn't dribble. I know because I still remember watching those Celtics teams and cringing while I prayed for TA not to dribble the ball off his foot every time he tried to drive. Tony Allen (as a ball handler) was on Avery Bradley level, at best. Smart isn't an elite dribbler - he's not good enough at it to give him an advantage over opponents. But his handle is solid enough that you can trust him to bring the ball up the court under heavy defensive pressure, and not bounce it off his foot.
Allen was completely lacking in play-making ability. His basketball IQ on the offensive end was poor, his court vision was poor, his passing ability incredibly basic. As with his ball handling skills, I would has his passing ability was about on Avery Bradley level. Put him under any kind of defensive pressure and he's just as likely to throw the ball out of bounds as he is to actually get it to a teammate. Marcus Smart is no CP3, but he has solid court vision, decent basketball IQ, and he has the ability to make solid passes on a consistent bases, and even to wow you occasionally with the odd fancy pass that you didn't see coming.
This why I say Smart and Allen are completely different players.
Allen is a guy I categories as a defensive specialist/role-player because for the most part, that's about all he does. Sure he's capable of scoring, but if you ever have to depend on Tony Allen as your scorer you are in a LOT of trouble. Like Avery Bradley, you are also in a lot of trouble if you try to ask Tony Allen to run your offense on a regular basis.
i don't classify Smart as a defensive specialist/role-player because he has a skill set that is versatile enough that you can start him at the PG spot. While Defense is his greatest strength, he can do plenty of other things too - he can handle the ball, he can hit the open three, he can find the open man, and on occasion he get tot he basket (something I suspect he'll be more effective at this year).
I think it's more likely that Smart ends up a Rodney Stuckey type.
Who would you rather have... Zach Randolph in his prime or Rodney Stuckey in his prime? I don't think either Randle or Smart will be perfect. It will be interesting seeing them develop, though.
I don't see Smart as being much like Rodney Stuckey. I don't recall Stuckey ever being half the defensive player Smart already is.
The key word when it comes to Smart's defense is 'dominant'. Marcus Smart legitimately has the ability to
dominate games with his defensive pressure. He is the type of guy who could walk out of a game having not scored a point, and still get praise for the impact he had.
This is why I refer to Smart to a mini-Iggy. Iggy was never an elite scorer (only 14 Points Per 36 for his career) but he could score when needed. He's not a great shooter, but he can still break an opponents heart with a big clutch three. He's not a natural passer / ball handler, but he can run your offense if you need him to. He's got an outstanding motor and outstanding leadership skills (much like Smart) and he can absolute dominate a game with his defense (much like Smart). Both guys are very strong, physical players who have solid size for their position, and who can play 2-3 positions when called for.
If you look at Iggy's career Per-36 numbers (14 points, 5.5 reb, 4.7 assists, 1.7 steals, 46% FG, 33% 3PT, 72% FT) then that looks like almost an exact clone of the type of stat-lines I expect Smart to be putting up over his career. On their own those stats look unspectacular, but anybody who has watched Iggy play knows that the impact he has on the game has typically far exceeded what shows up in the box scores mostly because of his hard nosed defense, his outright hustle, and his positional versatility.