Not an optimizer to a large degree myself, but, out of curiosity ...
I know vital strike is generally an underwhelming feat, but what is people opinions of taking it for an arcane archer? When they use an imbued arrow they only get one attack anyway - would it be worth it to add more damage to that one attack or still a 'wasted feat"
1.)I don't think Vital Strike is a wasted feat because taking it means that you now can use a move action to do something and can make an attack at roughly the same damage as 2 attacks (except you don't get STR. Power Attack, or any other bonus damage doubled), which I think was the intent of the feat.
2.)It seems like a good application of the feat to do double arrow damage+AoE damage/effect+1 enhancement+elemental property at high enough level. What spell, if you don't mind my asking, would you be using?