This is Baja's list of the best powers for heroic tier.
Ardent - Mindlink Strike - 2 augments - close burst 1 ~2w and one 1w
Cleric - Moment of Glory - knock an enemy away and down and sustain resist 5 for all party members
Druid - Grasping Tide - at-will, burst 1 in 10 vs fort, d6+mod, restrict enemy movement or prone
Druid - Grasping Claws - because this
Fighter - Come and Get It - close burst 3, brings enemies to you for 1w damage
Fighter - Thicket of Blades - 3w damage close burst 1 following Come and Get It
Fighter - Rain of Steel - spend one minor to deal 1w to any enemy starting near you during the encounter
Fighter - Bedeviling Assault - 2w+mod, 1 free mba against that target per round for the encounter
Paladin - Astral Thunder - Close burst 3, 2d8 and attack penalties, as an encounter
Paladin - Wrath of the Gods - Close burst 1 utility minor action, buffs damage by charisma mod for encounter
Ranger - Twin Strike - two attack at-will, ranged or melee
Ranger - Spitting Cobra Stance - 1w any enemy that moved toward you
Rogue - Knockout - knock enemy unconscious
Rogue - Gloaming Cut - at-will 1w + sneak attack while hiding continuously
Sorcerer - Adamantine Echo - AoE w/ongoing damage, +2-7 ac bonus w/support
Swordmage - Sword Burst - close burst at-will vs reflex
Wizard - Sleep - knock enemies unconscious
Wizard - Instant Friends - make your enemies cooperate
Wizard - Summon Succubus - debuff enemies, dominate enemies, fly
Wizard - Visions of Avarice - burst 5 in 10 trap your enemy in a zone sustain minor
Warlock - Hellsworn Blessing - give an ally 2d8 extra damage
Warlock - Decree of Khirad - almost dominate close blast 3, consolation damage
Warlord - No Gambit is Wasted - 2w+mod and an ally can retry a power
Warlord - Stand the Fallen - 3w+mod and allies healed surge+mod
Warlord - Lamb to the Slaughter - Pull enemy 5, enable three allies a free charge attack
The list is updated regularly based on reasons for and against powers.
I made the list for fun so keep this thread fun.
Format for suggestions:
promotion or demotion
class - power - reason
person who originally suggested the power or acknowledge you did not look up who
The last part is to insure you know that I am not the sole contributor.