Kansas and Kentucky look like the best teams to me right now, because they have fewer question marks than other teams. As has been pointed out in other articles, Kansas has 5 players on their current roster who have averaged more than 12 points per game in a single season (Doke, Vick, Dedric, KJ, and Moore). What's more, those 5 players naturally fit into a typical looking starting 5. I'm not saying they will start, but they could if they had to, and I'm willing to wager we'll see those 5 players on the court together a fair amount this season. So you have that as kind of a base.
Now you add Dotson, Grimes, Garrett, De Sousa, and McCormack and you have another talented, albeit unproven starting 5. Oh and you also have Lightfoot and Agbaji. For Kansas to reach their full potential this season, their younger players will need to play well and live up to the hype, which they seem to be doing for the most part; Grimes was the FIBA U18 mvp; Dotson is very fast; Garrett has been working on his shot; McCormack works hard and has looked good; De Sousa ended his season on a high note. But even if all of those players have a rotten year, which won't happen, Kansas is still left with a capable and proven starting 5. I'm sure that's what a lot of these coaches and writers see right now when they look at Kansas - a safe team with a ton of depth that still has a lot of room for growth. My biggest worry with Kansas is the guard play. Bringing the ball up the court, handling the press, running the offense, getting the ball to the right player, will be the responsibility of freshman and sophomores. Kansas most experienced ball-handler is a redshirt sophomore.
Kentucky is similar to Kansas. They have enough depth for 2 starting 5's that would be ranked in the top 25, some experience (though not as much as Kansas), and a lot of talent. Experience could still be a problem for Kentucky, but their depth makes it less of an issue. And it looks like they'll have some decent 3-point shooters this season too. By far, Kentucky is the team that most worries me as a Kansas fan.
Duke doesn't have the depth that Kansas or Kentucky do. They are hyped because they have the Top 3 freshman in the country by recruiting rankings (Barrett, Reddish, Williamson). They are all good players, but they are freshman and they all play similar positions. Duke is lacking in point guard depth. Their starting point guard will be Tre Jones (another 5-star freshman). If he struggles or gets injured, Duke will rely on Jordan Goldwire (who played 6.5 minutes per game last season) to handle point guard duties. They also have nowhere near the big-man depth that Kansas and Kentucky have. Coach K is high on Marques Bolden (he says he can be as good as any big man in the country next season), but he only averaged 12.9 minutes, 3.9 points, and 3.6 boards per game last season. Other than that they have Javin DeLaurier (12.7 minutes, 3.4 points, 4.0 boards), Antonio Vrankovic (4.7 minutes, 1.0 points, 1.1 boards), and Justin Robinson (4.8 minutes, 1.4 points, 0.6 boards). Even if Barrett, Williamson, and Reddish live up to the hype, I'm not sure Duke can be as good as Kansas or Kentucky without Jones and Bolden playing well too.