My First Recipe -Advice and Opinions Needed!

I created my first recipe and would love some tips/advise/opinions. It is a Double IPA, I am going for a strong hop aroma but not extreme bitterness coplimented by malty backbone. I want a complex hop profile so I went to my lhbs and picked out a bunch of hops then entered them into beer smith to create the schedule I now have.

10 lbs Breiss Munich Golden Light DME
.5 lbs Carmel 20
.75 Munich 10
1 oz Columbus (15.8%) - 60 min
1 oz Magnum (13.1%) - 45 min
.5 oz Centennial (8.8%) - 20 min
1 oz Cascade (5.9%) - 15 min
.5 oz Centennial (8.8%) - 10 min
1 oz Citra - (12.1%) - 5 min
1 oz Simcoe - (12.2%) - Flame Out
1 oz Amarillo (9.3%) - Dry Hopped
.5 oz Citra (13.4%) - Dry Hopped

Estimated O.G - 1.089
Estimated F.G - 1.022
IBU's - 59.2
Estimated ABV - 8.68%

I am debating whether to add 5lbs of the DME at the beggining and then 5 lbs at flame out, or just all 10 lbs at the beginning? I want the best hop utilization. My last IPA I added all at the begining and it came out pretty dark, I think it was due to the sugars from the DME carmalizing (It is delicious though).

Thanks!

If there's even a question of hop utilization, add the DME later. Hell, I'd even add only 1/4 of it first since you'll have a wort going already. I feel like DME doesn't really benefit from boiling unless you're really going for a caramel flavor, but it seems you have those possibilities covered in the rest of your grain bill.

Seven different hops - let me know how it turns out, I may have to copy you once I get a mash tun going!!