Double Milk Chocolate (Sweet Stout) opinions

Hello I'm working on a partial mash recipe for a double chocolate stout and would be open to some opinions. The thing I'm curious about most (in this iteration) is how the crystal will taste and if I will be able to taste the range of the four. Any one have any experience with using 3+ crystal malts? I am sitting on more than a few vanilla beans, but I figured this one was complex enough already. I with brewing in a bag my efficiencies are al ready not the greatest. I max out around 12lbs any more and my efficiency down down the ****ter; I usually like to keep it around 8-10lbs. I am open to scaling some of the items down or removing them outright.

Hopville . "Mouth Overload" Sweet Stout Recipe

% Lbs OZ Ingredients
26% 4 8 Muntons Plain Extra Light DME 34 7 ~
17% 3 0 American Two-row Pale 37 1 ~
11% 2 0 American Six-row Pale 33 1 ~
9% 1 8 Briess Chocolate 350 L 34 350 ~
6% 1 0 Barley, Flaked 32 1 ~
6% 1 0 Briess Carapils 34 1 ~
6% 1 0 Milk Sugar (Lactose) 35 0 ~
6% 1 0 Flaked Oats 33 2 ~
6% 1 0 American Munich 33 10 ~
3% 0 8 Brown Malt 32 65 ~
1% 0 4 American Crystal 80L 33 80 ~
1% 0 4 American Crystal 60L 34 60 ~
1% 0 4 American Crystal 40L 34 40 ~
1% 0 4 American Crystal 120L 34 120 ~

Hops
boil 90 mins 1.0 Willamette pellet 5.5
boil 1 min 1.0 Willamette pellet 5.5

Chocolate
boil 0 min 4 ounces Cocoa Powder
secondary 14 days 6 ounces Cacao Nibs
bottling 35 days 12 ounces Godiva Vodka
bottling 35 days 2.0 liquid ozs Chocolate Extract (to taste)

That is one complicated grain bill! The 1.5 lbs of chocolate malt seems like a lot to me and I think you would want to use some roasted barley, also. You may want to have some roast-y flavors to help balance the lactose and chocolate, perhaps.

For what its worth, I use around a half lb of both chocolate malt and roasted barley in my basic sweet stout recipe - its not a chocolate stout, though. If you want to look at the recipe, its here sweet-stout

Adding the chocolate at bottling sound interesting. I've never done that with chocolate, but have with herbs, in a tincture or potion with vodka. This should be an interesting experiment!

Ahhh, I see the "Kitchen Sink Stout"