Belgian Dubbel/Dark Srong advice please

[OptimusJay]

Working in Beersmith to create this Belgian Dubbel/Dark Strong recipe. A local microbrewery, Greenbush, has a brew called Isole. On their website they list the ingredients but not measurements. I used an existing Dubbel recipe from BS and made adjustments so that the grain bill has the ingredients needed. Where I need advice is on the qtys of the grainbill. I looked at several Dubbel recipes and used my best judgement as far as how much of each to use. I welcome all feedback.

Batch Size: 5.25 gal
Boil Size: 6.72 gal
Color: 20.8 SRM
Bitterness: 26.6 IBUs
Est OG: 1.077 (18.5° P)
Est FG: 1.014 SG (3.7° P)
ABV: 8.2%

11 lbs 8.0 oz Pale Malt (2 Row) Bel (3.0 SRM) Grain 1
8.0 oz Aromatic Malt (26.0 SRM) Grain 2
8.0 oz Biscuit Malt (23.0 SRM) Grain 3
8.0 oz Caramel/Crystal Malt - 20L (20.0 SRM) Grain 4
8.0 oz Caramel/Crystal Malt - 60L (60.0 SRM) Grain 5
4.0 oz Chocolate Malt (450.0 SRM) Grain 6
4.0 oz Special B Malt (180.0 SRM) Grain 7
1 lbs Candi Sugar, Clear (0.5 SRM) Grain 8
1.0 oz Styrian Goldings [5.4%] - Boil 60 min Hops 9
1.0 oz Styrian Goldings [5.4%] - Boil 20 min Hops 10
1 pkgs Belgian Ale (Wyeast Labs #1214) Yeast 11

60 minute mash @ 152F, batch sparge
1.5L starter for yeast

Thanks,
Jay