Please critique my RIS

Batch Size: 5.00 gal
Boil Size: 5.72 gal
Boil Time: 60 min
Brewhouse Efficiency: 70.00

15.00 lb Pale Malt (2 Row) US (2.0 SRM) Grain 72.71 %
1.50 lb Rye, Flaked (2.0 SRM) Grain 7.27 %
0.75 lb Black Barley (Stout) (500.0 SRM) Grain 3.64 %
0.75 lb Chocolate Malt (350.0 SRM) Grain 3.64 %
0.63 lb Roasted Barley (300.0 SRM) Grain 3.05 %
2.00 lb Brown Sugar, Dark (50.0 SRM) Sugar 9.69 %

1.00 oz Pearle [6.70 %] (60 min) Hops 15.2 IBU
1.00 oz Chinook [13.00 %] (60 min) Hops 29.6 IBU
1.00 oz Pearle [6.70 %] (30 min) Hops 11.7 IBU
2.00 oz Cascade [5.50 %] (15 min) Hops 12.4 IBU

Est Original Gravity: 1.110 SG
Est Final Gravity: 1.028
Estimated Alcohol by Vol: 10.86 %
Bitterness: 68.9 IBU
Est Color: 54.9 SRM

I'm planning on mashing this at 154 and pouring the wort onto an WLP005 yeast cake.

The reason why I'm going with the 2lbs of sugar is because my mash tun is 36 quarts and can't handle much more grain than I have here.

Any thoughts on this recipe?

Wow... that's massive. You'll need to mash considerably lower than 154 if you want to hit your FG. Not sure how the rye fits in there, but could be interesting. I'd considerably up your IBUs.... also the 15 min. hops will be lost in that much malt...

I would up the IBUs another 10 or so and mash around 148 to create more fermentables. I've never really thought about putting rye in my RIS, but yea, it might be interesting.

I just did an american stout a week ago and added a bit of rye to make it a little more complex/spicy it's bordering on an RIS I can't wait to try it.
You recipe looks good give it shot see how you like it when it's done and adjust it next time if need be.

Pat