Honestly, who take's Unicorn's Horn over Armathor's Step or one of the movement powers anyway unless you are running leaderless? Leaders' encounter heals "recharge" at the same rate and are much more efficient. Surge allocation is basic resource allocation and if you've waited an hour and a half already, you might as well extend it to get dailies back too.
1) Note that Leader's encounter heals cost a Surge. Removing the primary cost component - surges - makes it vastly more efficient than Healing Word or anything else. Now, this assumes you have the time available to make use of it - but in many, many situations you do, and it throws off the dynamics of the system.
2) You only get one extended rest a day. If you get into a fight at noon, and spend an hour using Unicorn's Horn to heal up after it, you'd have to wait another 18 or so hours to get in your Extended Rest. Finding an hour of rest time is a lot easier than simply wasting the entire day after every fight.
It might not be the end of the world, but I think your counterpoints against it aren't really valid ones within the actual mechanics of the game.
This doesn't make any sense. Designer intent is designer intent. You can't argue that the designer's intent was other than what the designer stated his intent to be by pointing out that his intention wasn't wise. There's some serious confusion about textual interpretation going on here.At the end of the day its blatantly retarded to say that rain of blows is supposed to be 4 attacks (all with your str mod added to damage). So while "God" can say it was supposed to be so, that doesn't mean that "God" isn't wrong in this situation.
This doesn't make any sense. Designer intent is designer intent. You can't argue that the designer's intent was other than what the designer stated his intent to be by pointing out that his intention wasn't wise. There's some serious confusion about textual interpretation going on here.
I'm reasonably sure everyone here is aware that it works only when you hit. But even you recognize that it will be used when "he's sure he'll hit". See how it works when the human Paladin from Chauntea with Action Surge, a Lance of Faith power bonus, combat advantage and a Tactical Warlord ally crits in 4 of 5 encounters. Let's just say it isn't all that difficult to pull off.#3 righteous rage. read the power again, it is not an auto crit. It works 'on your next attack, if it hits, before the end of your next turn' If you're very next attack doesn't hit, you are out of luck, (even if you use rain of blows), and have spent a feat, a minor, your attack power, and your channel divinity for that encounter. It is awesome if it works, but it's not a sure thing. Granted the player will pick his shot for when he's sure he'll hit, but still, once invoked, he has until the end of his next turn. Awesome damage power, but not broken even for a striker.
It means you can't die from starvation and could live forever without eating or drinking, among other things. It may not have a big impact on your games, but it's pretty game breaking for some.