just from what we have seen in season 3 I'd honestly rank homelander as 90, Soldier Boy as 100, and Butcher at 80. I'm pretty sure Homelander could kill Butcher if the fight went on long enough, if nothing else once he finds out he is on Temp V he can just wait it out.
Soldier Boy, so far, is technically more powerful than Homelander because he went through years and years of testing without death, he has developed a new power which lets him depower supes (so that automatically makes him more powerful than Homelander), and he blacks out and goes feral with at least one trigger. The only thing we don't know is that "something" knocks out Soldier Boy, not Halogen (?) gas, and we don't know what it is or how effective it can be at larger doses.
The reveal that Homelander has a smeagol personality that "protects" him was interesting though, wonder if thats an even more powerful personality.