Pale Jackal
First Post
If you wanted to broaden this idea, what you could do is create a new category called "Recovery Actions". Similar to opportunity actions, you create a generic set and then your more specific actions.
Recovery Actions - These actions allow a creature to recover resources or negate conditions during a fight.
1) Once per encounter - You only get one recovery action per encounter.
2) Uses healing surge - Each recovery action requires the expenditure of a healing surge.
Second Wind - as is.
Greater Effort - Minor Action, allows you to recover an encounter power, and gives you a +2 to your next attack roll.
An interesting idea, but let's compare Greater Effort to Second Wind, using say, the Cleric's Level 1 Encounter Healing Strike.
Second Wind gets you a +2 to all defenses, and you get to spend a surge.
Greater Effort let's you, for a minor action and a standard action (and really, depending on your class, you have your minor action often available), gives you a roughly 50% chance to deal 2W + Str. damage and let's you heal Surge + Wis. So let's call it 1W + 1/2 Str. damage, and +1/2 Surge + 1/2 Wis. modifier.
I'm not going to say that Second Wind becomes useless, but I think it's perilously close to being obsoleted.
Using some level 1 numbers, say, a Human cleric with 18 strength and 16 wisdom, you can heal a guaranteed 6 HP, or you can have a roughly 50% chance of doing 2d8 + 4 damage (average 13 dmg.) and also heal 6 + 3 HP. Halve both of those: 6.5 and 4.5 = 11 HP of damage and healing.
That increases to ~12 HP if you took something like Weapon Proficiency: Bastard Sword (and I would take that over say, Toughness.) That's a 100% difference. Of course, this costs 2 healing surges, but doing damage sooner may save you additional HP.
As you level up, Second Wind might get better, but I do fear that you're making Second Wind almost redundant.