My first high gravity beer - Imperial India Black Ale

So this is the third beer that I've made and I decided to strike out and write my own recipe with assistance from BeerSmith 2. Here goes:

Boil Size: 4 gal.
Boil Time: 60 min.

Grains:
8 oz. Black Malt (500 SRM)
8 oz. Carafa II (412 SRM)
4 oz. Cara-Pils (2 SRM)
- Grains steeped in 2 gal. of water for 28 minutes at 155 degrees.

Fermentables:
3.5 lbs Light DME (mixed into 2 gallons water and added after steeping)
6.6 lbs Light LME (late addition at 15 minutes to go in the boil)

Hops:
1 oz Magnum (13.10% alpha) - 60 min.
1.5 oz Magnum (13.10% alpha) - 30 min.
1 oz Chinook (11.80% alpha) - 5 min.
1 oz Chinook (11.80% alpha) - 1 min.
1 oz Willamette (5.50% alpha) - 0 min (flameout)
.5 oz Kent Goldings (5.8% alpha) - 0 min (flameout)

Yeast: White Labs WLP550 Belgian Ale - 2 vials proofed for 30 mins at room temp

Est OG: 1.079
Est FG: 1.015
Est ABV: 8.6%

Brewed it up last night, originally wanted to use Citra hops instead of Chinook, but my LHBS didn't have any in stock. The Kent Goldings I had leftover from a batch two weeks ago so I threw them in. Can't wait to see how it tastes!

Probably should have made a starter for this batch, but brewing was pretty last minute so I didn't have time, hence two vials of yeast instead of 1.

Any thoughts?

Looked pretty good until I got to the yeast.

Going to be interesting.

I like that yeast, but have never used it in a roasty beer. The darkest I've gone with it is a Dubbel that I have in the fermenter right now.

Hoping that it will give some unique character to the beer - I typically like beers that don't smell the way they taste which should be what this beer turns out to be. Time will tell!