I'm in love with hybrid leaders. These days, my two LFR characters are:
• Illyria Stormborn, a Stormsoul Genasi Ranger/Warlord-multiclassed Spiked Chain user/Infernal Strategist who hands out ridiculous bonuses while frostcheesing enemies four or five times a round between Twin Strike, Minor Actions, Immediate Actions, and Free Actions from other Leaders.
• Aegon Stravinsky, a Stormsoul Genasi Wizard/Warlord/Academy Master who drops enormous Thunder-Psychic Winged Hordes that wreck the enemy while summoning up assorted monsters of his own.
And I'm playing in a Dark Sun game where I run:
• Amiri, an Elf Ranger/Shaman/Elemental Priest Theme-multiclassed Druid who murders things from half a mile away while a small horde of elementals help out my party.
Other characters that I played in LFR for a while included:
• Random, a Tiefling Cunning Bard who relied on Stirring Song of Baator plus a flaming weapon for a massive torrent of temporary hit points.
• Nowhere, a Tiefling Fire Wizard who had fun taking down a cult of insane fire worshippers.
• Quinn, a Human Shielding Swordmage/Artificer/Coronal Guard with big thundering Sword Bursts.
• Revelation, a Tiefling Paladin/Warlock/Turathi Highborn with lots of AoE marking and Marked+Eyebite hilarity.
• Lanna Gearsong, a Dwarf Avenger/Cleric.
• Iriana Moonrise, an Elf Ranger/Cleric/Sharpshooter.
• Grendel, a Half-Orc Tempest Fighter with a Spiked Chain.
I also dinked around with a Dwarf Battlemind and a Human Ardent, but wasn't very impressed, had some fun with a Shifter Runepriest, and tried out a Halfling Sorcerer/Bard, a Dwarf Invoker/Cleric, and a Dwarf Warlock/Warlord with Hammer Shock and Hammer Rhythm.
So, yeah, as you can tell from the cloud of hybrid-multiclassed mashups, I'm not really the type to go for Essentials classes.