If you are looking for a session beer I think your IBUs are going to be overpowering and throw the balance of the beer out of whack. I would stick with a 1:1 OG to IBU ratio at most. Also 9 ounces of hops in a 4.5% beer could for many folks be the opposite of a session beer because your palette could get worn out. I would suggest moving your IBUs into the 40ish range and using about 2/3 of the hops you initially thought of. Also the amount of specialty grains you are using are a fairly high percentage of your total grist. From my experience, you should have no more than 15-20% specialty grains in this type of beer, so that would put you in the 1.75 pound range for your crystal, chocolate rye, carafa, and flaked rye. Just my 2 cents!
Life is too short to drink crappy beer@
Kegged: Super Hoppy Red Ale, IPA
Bottle: Barleywine, Belgian Chocolate Red
Fermenting: India Brown, Pale Ale