My Accurate Smokeless Powder manual is the #1, so I admit it is a bit dated ( 1994 ). But the data in that manual is no where near 27 - 30 grains of 1680. Top load for a 200 gr jacketed bullet is 21.5 grs.
I load the 357 Max in a Contender with 10 inch barrel. I use a 200 gr bullet I cast from a LBT mold. I have done a modest amount of work with 1680 in the 357 Max. I have gone as high as 25.5 grs of 1680, which chronographs from the 10 inch barrel at 1617 fps. For best accuracy and comfort of shooting, I have settled on 25.0 grs of 1680, which chronos at 1522 fps in my gun. It is still a handful, but drops the whitetails just fine.
I would urge some caution in trying to make the 357 Max perform like a 35 Rem. The Max is a fine cartridge in the single shot platform .