Unit Strength is the key victory determinant in three of the COK scenarios. It has been pointed out that there are 12 scenarios and so Unit Strength is not necessarily a dominating (see what I did there) factor. However, I believe that Invade, Dominate and Control will tend to be overrepresented in scenario choices as they are significantly different from the other more "Loot/Pillage" based scenarios.
Locally we are seeing about 1 point of Unit Strength per 110 points. This means you can expect 18 Unit Strength armies at 2000 points. This is based on a very small sample size but you need to start analysis somewhere.
Recently the TO from Clash of Kings at Adepticon posted nine of the top ten lists here
By my calculation the event was 2250 points so applying my modifier you'd expect around 20-21 Unit Strength lists. The actual unit strengths were as follows:
- Orcs - 22
- Goblins - 26
- Ogres - 22
- Undead - 22
- Basileans - 20
- Goblins - 24
- Twilight Kin - 14
- Goblins - 29
- Dwarfs -18
EDIT: Found out that Invade, Dominate and Control all were played. So heavy bias to US.