Rough draft for my rankings of PF's.
Tier One: Icons
1. Giannis
2. Davis
Tier Two: Superstars
3. Horford
Tier Three: Stars
4. Siakam
5. Draymond - I think he'll have a bit of a bounce-back year
6. Griffin - I think he'll drop off this year after the injury
7. Sabonis - super underrated
8. Gallinari
9. Porzingis - this is projecting based on him being healthy
Tier Four: Great Starters
10. Millsap
11. Gay
12. Jerami Grant
13. Thad Young
14. Marvin Williams
15. Gibson
16. Isaac
Tier Five: Great scorers
You might notice that I've ranked the great scorers lower at PF than at other positions; this is intentional, since I think PF (and especially center) have a larger impact on overall defense than guards and wings, since they help more in the paint and at the rim.
17. John Collins
18. Love
19. Bagley
20. Jackson Jr - needs to earn his defensive reputation or improve as a rebounder to move up
21. Markkanen
Tier Six: Solid Starters, good on both ends of the court
22. Olynyk
23. Zach Collins
24. Aaron Gordon
25. Marcus Morris
26. Jamychal Green
27. Nance
28. Saric
29. Bjelica
Tier Seven: Good defenders, not great on offense
32. PJ Tucker - I don't understand how some of his impact stats are so good
33. Aminu
34. Ilyasova
35. Kleber
36. James Johnson
37. Kyle Anderson
Tier Eight: great scorers, bad on defense and at rebounding
36. Rabb
37. Kuzma
38. Miles Bridges
39. Jeff Green
40. Jabari Parker
Tier Nine: good defenders, useless on offense
41. DJ Wilson
42. Jordan Bell
Tier Ten: inefficient volume scorers, bad on defense
43. Wood
44. Giles
45. Portis
46. Lyles
47. Niang
Tier Eleven: Meh players
48. Maker
49. Tolliver
50. Muscala
51. Scott
52. Markieff Morris
Thanks for reading! Let me know what you think