Going to higher doses is a lot easier with the companion nutrients in place. Magnesium 300-600 mg, selenomethionine 200 mcg, Vit C 3000 mg spaced out, 1/2-1 tsp unprocessed salt with plenty of water. ATP Cofactors has generous amounts of Vit B2 and B3, but at least a good B complex is useful.
I wouldn't go higher than 150 mg Iodoral or Lugol's before being sure you can handle all the iodine. 300 mg is their upper limit. SSKI (saturated solution of potassium iodide) is a terrific partner to Iodoral and Lugol's to get to higher doses. The dose is determined by whatever bromide and fluoride detox you can handle. It does happen that more Iodine -- especially SSKI -- can make the process easier, within limits.