You should not have to align the blades with the fletching. Whether shooting with a drop away or Whisker Biscuit, I have been fletching vanes (first Blazers, then Vanetecs) with the max helical I can apply. No doubt feathers give you even more control, but I have been pleased with broadhead accuracy out to 40 yards with my setup. I usually use Bohning Quantum, which is a "superglue" type. Superglues seem to bond two surfaces together quickly, yet the excess is still liquid when the vanes are bonded. You can then wipe the excess away. I try to use as little as possible, but still get a little squeeze out if I use enough to get a good bond. With feathers, I use Fletch tite or Saunders NPV.

The reason your Stingers shoot better lined up with the string is that the main flex of a release-shot arrow is up and down. I still recall (with chagrin) the time I thought I had my bow tuned well. I was shooting Bear Razorhead lites, without the bleeders in. At 30 yards, I could pretty much pick a specific spot on my Aim-Right deer target and hit exactly there with the Razorheads or field points. The Razorheads were lined up vertically (with the string) A few days before the season started, I decided to sacrifice a few of the fragile bleeders just to make sure they shot the same with the bleeders in. The arrow dove down and hit the deer target in the front leg! Took the bleeder out and spot on. Put another bleeder in, under the belly! Had to do a little last minute scrambling that year. I made sure that didn't happen again, and that I was absolutely sure of my setup well before the season started.