Jackson not tier 2. I prefer most you have at tier 3 to him. He is too raw.
Comparing Jackson Jr. To the bigs/swings in my tier 3 Bamba, Bagely and Porter Jr.
1. He is the youngest player in the group at only 18 1/2. Bagely is the next youngest at 19 while Bamba and Porter are almost 20.
2. He is the best over all defender in the group. Statistically he averaged 5 blocks per 36mpg compared to Bamba's 4.3. Outside of the stats he is clearly the best perimeter defending big in this class. His ability to switch to smaller players and provide elite rim protection places him in a very unique and desirable archetype.
3. Ill exclude Porter JR due to his small sample size but compared to Bagely and Bamba he is leading the grup for having the most potential as a floor spacer. Though his shot has a slightly different look to it he shot 39% on 2.7 3PA and .79% on 3.8FTA compared to Bagely who despite playing over 10 more mpg shot the same 39% on only 1.8 3PA and 62% on 6.3 FTA, Bamba was 27% on 1.73PA and 68% on 4FTA.
Looking over past college players I am having a hard time finding a player who shoots as many 3s as Jackson at nearly 40% while also averaging 2.5 (let alone 5) blocks per 36. The two best comps I can find are Bosh 1.7 3PA @ 47% and 2.5blks per 36 and M Turner 3.0 #PA @ 27% and 4.2blks per 36. In this years class Jontay Porter is actually another player who falls into this grouping as he averaged 2.5blks per 36 and shot 36% on 4.9 3PA. However he is no were near the level of athlete that Jackson is.
He may be raw as any 18 year old would be but he seems to play within his game and doesn't try to over extend himself. He really has the ideal mix of skills for a modern day big man. Given his young age and NBA pedigree I am confident to predict that he floor as a prospect is that of a Serge IBaka like role player.