Strongest heroes in the game. Maiev and Zeratul are Heavily based on mechanical skill.
Solid picks. Some of these heroes are Tier S in the right hands or MMR range (IE Azmodan, Mal'ganis, Lili and Zuljin are Tier S in lower MMRs, Garrosh, Samuro and Tyrande are Tier S in Master+.
These heroes either require a lot of skill or game knowledge or are very map or matchup dependent, or are better in either the highest or lowest parts of the ladder.
These heroes are only good if they are played in their very niche situations or are being played by a 1-trick, or are strong in the lowest ranks of the ladder.
Bad heroes. Even 1 tricks are at a disadvantage. Imperius I have no idea.