To avoid a huge wall of text, this page has been split into several sub pages. We'll deal with At-Will powers here. If you're Int based, take Overwhelming Strike, and either Bond of Censure or Bond of Retribution if you wish to take advantage of Radiant tricks. If you're Dex based, take Overwhelming strike, and ... um. Avenging Shackles? Bond of Pursuit? Focused Fury for the ranged attack? Humans likely take Radiant Vengeance as their third at will.
Bond of Pursuit (PHB2)
Free shifts if the victim runs. I don't like it for hitting your target because it might not move if it's knows it's giving you free movement, and many targets won't run anyway. But the movement takes place after his turn ends, so Artillery that wants to shoot you may still move. And then you can shift around them. Note when you get the free movement: using it on an OA via HBO won't work the way you think it will. (SarxMarksman).
Bond of Retribution (PHB2)
If you get attacked the victim takes even more damage, but only once per turn. I think it's usually a trap, but sometimes might amplify the damage to the target. Use with caution, and watch what the DM does when you use it. Important note: It's got the Radiant keyword, which may be important. See the Radiant Feat package, especially the crit-based feats.
Domains: Fate Strife War
Focused Fury (DH2)
Ignore the kicker: it's a trap. (If you can use it, you didn't get your oath rerolls). The only value is "I want to make ranged weapon attacks, and my Dex sucks". If your Dex doesn't suck, then you take Distant Vengeance instead (rerolls are about equal to +4-5 to hit, so as long as your Dex is closer than 6 to your Wis, you're better off getting within 10 and using your crossbow)
Leading Strike (DP)
Give an ally bonus damage equal to your intelligence modifier. The main problem is your allies are unlikely to be as accurate as you are, so it would have been nicer if you had that bonus damage. But still, that's the only at-will power with extra damage, so that raises it up a notch.
Domains: Civilization Freedom Protection Hope Knowledge
Overwhelming Strike (PHB2)
Move the target around, and move you around. Good for tactical maneuvering, especially pulling enemies out of corners. Unfortunately, does the move after the attack, so you can't use it to get Oath for the current attack. (Note: the maneuvering is optional: PHB2, p219). The key value to it isn't the straight power, it's the add-ons. The Skill domain allows you to use this as a Basic Melee attack, which is a really good feature . Strength domain adds static damage. Deadly Draw adds combat advantage.
Domains: Storm Wilderness Darkness Earth Madness Torment Change Poison Strength Trickery Skill
Avenging Shackles (D382)
A ranged power that uses your implement, and does not come with a reroll. But it slows, and targets will, and can be used as a basic attack. Which means, if you take the Distant Vengeance feat from the same issues of dragon, it does come with a reroll . (In compilation they changed the Basic Attack verbage to make it clearer that it worked.)
Bond of Censure (DP)
It's a ranged power that uses your implement, but then gives you a reroll anyway. And it has a large pull for an at-will power, (Int based). Note you'll quickly have a pull that exceeds the power's range (unless you have a Symbol of Divine Reach or a Astral (superior) Holy symbol), and so not be able to use it all. The Horror.
Domains: Undeath Justice Destruction Luck Moon Winter Sea Tyranny
Radiant Vengeance (PHB2)
Ranged 10 and Temp HP! Yay! Uses the holy symbol you rarely use, and doesn't allow you to roll twice. Boo!!! Use as a ranged intro on those turns you can't get in fast enough.
Domains: Creation Love Arcana Death Life Sun Vengeance