1. For some scientific reason, later additions of DME, LME and sugars are better if you are using a lot of hops in your boil. Someone could explain it better but it's science.
2. You will get better results if you are able to do a full boil and minimal top-off water at the end. That way you aren't watering down your IBUs.
3. I would avoid some of the early additions and push them to the last 15 minutes of the boil. This will give you more aroma and flavor and less pure bittering, which after a certain point is a waste of hops.
4. I would hops something like this:
- 0.5 oz. Chinook @ 60min
- 2 oz. Cascade @ 15min
- 0.5 oz. Chinook @ 15-10min
5. It looks as if you are only dry hopping with 0.5 oz, or not dry hopping at all. If that is the case you are going to be pretty disappointed in the aroma on this brew. Dry hopping is a cornerstone of IPA brewing and helps immensely with the aroma. I would recommend letting it ferment out in primary and then dry hop it in secondary for 14 days as follows:
- Blend 1 oz of Cascade and 1 oz of Chinook
- Add 1 oz. of blended hops to secondary for the first 7 days
- Add remaining ounce for another 3-5 days
- Siphon to bucket and bottle
I believe this method would give you a better aroma and hop flavor.
Sorry if this is confusing or I come off as a jerk. I am passionate about hops, hopping and IPAs :P