Nice spreadsheet, Mercy Stroke with its 250 Potency would be like letting off a Sidewinder. Blood for Blood could work too. Both are near lvl 30 abilities though... I guess to have a decked out DD Archer , you will spend plenty time with other classes.
I wouldn't worry too much about Mercy Stroke since ARC already has access to Misery's End. It's a bit weaker than Mercy Stroke, but it doesn't require you leveling another class to 26 to get. Blood for Blood, on the other hand, is totally worth going after. Both ARC and BRD can cross-class it.
One DPS ability ARC does lose out on, however, is Rain of Death
. So long as you're not accidentally waking something up, Rain of Death seems pretty awesome.
Like several others, I would love for SE to add in RNG. I'm not a huge fan of songs, and I would rather have additional attacks instead. Still, with the way BRD is set up now, I won't mind having to sing the occasional tune.