1.Do the whirlpool additions as you suggested. Stop chilling around 160-175F, add the hops and give it a whirl. Let it rest for 15-20min. before you resume chilling.
2. Dry hop at room temp. Extraction reportedly works much better that at serving temp. My only experience here is that keg additions have not been as effective when I dont let the keg warm up first. (if its already been chilled)
3. Multiple dry hop additions. I know Firestone Walker does this and so does Jamil at his brewery. Jamil explained it like this... You add large quantities of hop material and a lot of it settles right to the bottom and is buried by other hop material or even yeast that may still be crashing out. Once buried and no longer in contact with the beer it does not extract any more flavor/aroma into the beer. Multiple smaller additions allow better extraction by avoiding this situation. I've seen nothing objective on this but couldn't ignore it considering who practices it and went ahead and tried on my session APA. I added 1oz per day for 4 days and crashed on the 7th day. The aroma in that beer was as good as any I have made. (it also included substantial late hopping and a whirlpool addition)
4. Crash out the yeast first. I have read/heard multiple times that the yeast will bind to hop resins/oils and crash them out when they drop. I can't say I have noticed a big difference between doing this and not doing this but it makes sense and if I have the time I will do it. Might also be a good argument for using english yeast... again like Firestone Walker does.