I would remove the dark wheat and cara 300. Biscuit and black malt may not hurt anything but I wouldn't use them myself.
My grist for a stout would be pale malt, brown malt, roast barley, chocolate malt and probably a bit of invert #3 sugar. To make it an oatmeal stout you obviously add either oat malt or flaked oats. How much depends on what you are trying to recreate. (and I'm always thinking in terms of traditional English styles)
Malted oats were patented by Maclay's of Scotland in the late 1800's and they are given credit for producing the first Oat Malt Stout which they marketed as the "greatest in the world". Until brewers Rose and Wilson took them to court but that's another story.
Other brewers seemed to have gotten around Maclay's patent by calling their product "Oatmeal" Stout instead of "Oat Malt". Many of them began using flaked oats after the Free Mash Tun Act in 1880 which allowed brewers to use non malted grains and adjuncts.
There was a pretty big difference in the amount of oats used between Scotland and the big London brewers. I've seen Maclay's recipes that use up to 20% oat malt. While the London brewers often used as little as 1%... some even less.
So if you want a full out Scottish oatmeal stout you could up the percentage of flaked oats to maybe 10% or a wee bit more. Much less if you are shooting for a London version.
Your hops may be a little low when compared to the historical record. An IBU of 36 to 42 would be accurate. As for the variety, yes Fuggle is fine. So are Goldings and even American Cluster for bittering. The English brewers imported American hops frequently but used them primarily for bittering since they didn't like their aroma or flavor. They did like continental noble hops very much though and I have seen recipes for oat stouts using Saaz in the late additions.
Hope it turns out well.
