I was playing last night and realized something that may be obvious to most, but it wasn't to me until last night.
Doing your Dreaming City stuff gains your the highest light/power items. For the past few weeks, I was leaving the Dreaming City stuff till the last minute. I realized last night this was idiotic.
If you do your Offer to the Oracle first, you get a bunch of high power items. Then as you do the rest of your dailies/weeklies, they'll be at a higher power level. I was doing this backwards. I would do the offer last, so I was cheating myself out of power level because I wasn't getting the benefit of those higher light items in my inventory.