Control how much Rhea/XL affects faces vs everything else

IMO Rhea/XL does a great job at upscaling stuff but it often goes too hard on faces, especially if they’re background faces or out of focus faces. It looks pretty good on ‘prominent’ faces (though it could still do with being toned down a little), so it’d be great if we could add controls that adjust how much the model affects faces and how much it affects everything else, so we can balance it more appropriately to the footage.