Honestly I think this game was a bit hit and miss with it's boss and weapons, but I think it made up for a lot of the game with how the Cossack levels and wily levels shook out. Like it more than 1 and 3, but a little less than 2. Here's the order.

8- Bright Man
7- Ring Man
6- Dive Man
5- Toad Man
4- Dust Man
3- Skull Man
2- Drill Man
1- Pharaoh Man