Daggermasters don't really come into it. Chances are AP will only be used to follow up on a knockout (as an example).
Also - using daggers is one of the worst things to do, because that 7d10 (superior crossbow) becomes 7d4
Except the superior crossbow is much less likely to crit if you're a Daggermaster. That kinda was the point I was making by mentioning the Daggermaster. And if you're going to use a big daily like Assassin's Point, you better have Meditation of the Blade running, so make that 7d6 (plus a good chance of dealing 10d8 extra, instead of 5d8 with the crossbow).
9[w] tho gives you +5 to hit -them-. And then +5 to hit -them- for the rest of the battle that stacks with that first +5 which is what we call 'Being an Avenger.'
You -really- underestimate the value of Oath. You're complaining that Avengers aren't accurate... when they are the most accurate class in the game. Oath does -amazing- things.
Once you factor Oath in, you'll see that it's not so bad -at all-.
No, you don't get the +5 on the Final Oath attack. The "Effect:" entry is listed below the "Hit:", meaning it is resolved after the attack. And getting a +5 bonus to hit your target is relatively redundant on a class, which only redeeming feature is that it's already good at hitting (and has good defenses), while the monster you attack can use that +5 bonus just fine to overcome your high defenses. That +5 to both of you is more of a downside to you than to the monster.
As for comparing damage, let's have an overview (all things being equal, with ranges going from the least plausible amount at heroic to the highest steady amount at epic):
Rogue: High attack bonus, 1d4 to 2d10 plus 2d8 to 5d8 damage
Avenger: High attack bonus (Oath of Enmity statistically equates a +4 bonus to attack rolls), 1d10 to 4d6 damage
Ranger: Normal attack bonus, two attacks, 1d8 to 2d10 damage twice plus 1d8 to 3d8 damage once
Barbarian: Normal attack bonus, 1d10 to 4d6 plus 1d6 to 3d6 damage
Sorcerer: Normal attack bonus, ranged, 1d8 to 2d10 plus 4 to 14 damage
Warlock: Normal attack bonus, ranged, 1d6 to 2d10 plus 1d6 to 3d6 damage
Doesn't look that hot, really. Now if you added the bonus damage from the Censures, we'd be talking, but alas, that is supposedly only a control tool...