A lot of the value from Daze comes from Combat Advantage and No Flanking.
Not to mention the fact that they can't make OAs. That's huge. A dazed enemy is just a tree when it's not his turn; you can walk right past him without fear. That's a bigger advantage than you realize.
If your foe chooses not to attack you in melee from within your threatening reach, the power does nothing.
See, I don't equate "does no damage" with "does nothing". If my Riposte encourages an enemy to go fight the Fighter instead of my Rogue, that action was worth it.
If the power misses, it has no effect (whereas piercing strike increases your chance to hit and deft strike can too, by providing a flank that might otherwise be impossible).
Sure, but that goes for all powers. They're all situational.
In a lot of cases you'll be pretty sure of a hit anyway and don't need the Piercing Strike to boost that. If I'm flanking with the fighter, the attack bonuses stack up high enough that I'm hitting on a 5 or 6 anyway (+4 dex, +3 proficiency, +1 weapon talent, +2 combat advantage = +10 at 1st level). Attacking Reflex isn't a huge benefit in that case, especially compared against the chance for a second attack.
If the power hits, but the riposte misses, it has no effect.
If the power hits and you kill your foe, it has no effect.
Making an attack roll and missing isn't "no effect". You got to roll it.
Anyway, this doesn't make any sense. If you kill your foe with this power, you would've done the same with Piercing strike or any other attack. Be happy with making a kill and don't complain about your power getting "wasted". That's like the fighter whining that his Tide of Iron is worthless when he drops the enemy with it because there's no point to pushing a dead enemy.
If you deliberately try to set up scenarios where you're the most favourable target for your foe despite the riposte... you get pounded into the ground. Rogues are pretty squishy.
That depends on how you build him. A brutal dagger-rogue is pretty much designed for close in fighting, and if you give him decent CON he's actually a good character. Yeah, he's a skirmisher, but he's not THAT squishy.
I mean, that's really the point here, isn't it? The power encourages the enemy NOT to hit you! It's not exactly a defense boost, but it makes attacking you a bad idea, which WILL reduce the number of attacks against you. (Remember: Monsters always know the results of a course of action. They know what'll happen if they're marked and don't attack the paladin, and they know what'll happen if they attack you after you hit them with Riposte Strike.)