None of our bigs are "efficient". Horford, Rob, and Grant all hurt our efficiency.
Given that Grant is shooting the lights out from deep (also finishing 85% near the basket LOL) and Rob finishes over 70% of his attempts I'm not sure what type of efficiency you're talking about here.
Even Al is money from inside 16 feet (75% near the basket and his midrange efficiency is pretty excellent). Not to mention that Al is still a very skilled passer and defender.
I certainly agree that playing Horford and Rob together is detrimental to the offense, but that's because double bigs is very hard to make work on offense in the modern NBA.
It is not about their individual statistical efficiency, it is that we lose some much skill and ability. Yes, RWill can do the alley oop dunk. Yes, Grant can hit a 3 if wide open and in the corner (not sure you want to count on that in a pressure playoff game) and yes, Al can make a shot or two here and there.
The room for improvement in our bigs is so great though. I would be fine with Horford and RWill as our Centers (never on the court together) and GWill as our 4th big/2nd PF, but we need a starting level PF with some skill, some punch to balance out our team and allow the team overall to be harder to defend, more dynamic.
An upgrade at PG would improve things some also but I see that as far less of a need, far less of a weakness.
Agreed on Smart. That said, I'd want us to go after a swing, not a PF. Preferably a Point Forward in the mold of Ingles/SloMo. Imo, Tatum is at his best when playing at PF. Traditional PFs aren't mobile enough to stay in front of him on the perimeter. This is a massive advantage in our favour, especially since Tatum can put the ball on the floor and create his own shot.
Tatum also has a size advantage now at the 3. Dude is massive.
Both are fine. A skilled (s)wing who can pass it, or just a small forward-type like Jerami Grant. We're just so slow, plodding and unskilled at the 4 right now.
Tatum has a size advantage at SF and a speed advantage at PF.
Size advantage means 2 things:
1. He can post up his opponenet. Post ups aren't efficient in the modern NBA.
2. He can shoot over his oppopenent. He already does that, but the shots aren't falling at a consistent rate.
Speed advantage means he can beat his opponent on the perimeter and attack the basket.
Tatum thrives as a PnR ball handler. Given that he's having a cold-shooting season, he has to mix it up a bit by driving to the basket more often out of the PnR. If so, he'll also get more open looks from 3pt range, hence he'll gradually improve his 3pt%. Assuming we want him to attack the basket more often, we have to maximize his speed advantage. Only way to maximize his speed advantage is to use him at PF.