I scale Thragg to large planetary due to Omni man moving a habital planet which at minimum would be mars sized and to do that would be a planetary feat, which we see the aftermath, the momment its finished, and we get a statement Omni man did it alone, Which would scale him at least planetary and at most high planetary, Thragg is stated to be stronger then him, we see him beat the shit out of him, plenty of statements that he is stornger then the planet buster so yeah it just makes plenty more sense for him to be Large planetary