I am working on my first EDH deck, generally designed for a multiplayer environment. I am working on something of a budget (I would be loathe to go over $150), but would like some general advice.
Your deck seems okay, maybe i would add more lands/mana sources. You have 33 Lands and 4 Mana source, 37 together. Increase the count at least to 40 (lands and ramp together).
My general is Niv-Mizzet, the Firemind, and the rest of the deck is
1 Arcanis the Omnipotent
1 Teferi, Mage of Zhalfir
1 Sphinx of Magosi
1 Vesuvan Shapeshifter
1 Tidespout Tyrant
1 Urabrask the Hidden
1 Dwarven Driller
1 Obsidian Fireheart
1 Guttersnipe
1 Galvanoth
1 Balefire Dragon
1 Nin, the Pain Artist
1 Jhoira of the Ghitu
1 Mindwrack Liege
1 Nucklavee
1 Gelectrode
1 Hypersonic Dragon
1 Izzet Chronarch
1 Goblin Electromancer
1 Djinn Illuminatus
1 Counterspell
1 Cryptic Command
1 Counterlash
1 Twincast
1 Brainstorm
1 Train of Thought
1 Omniscience
1 Arcane Melee
1 Archmage Ascension
1 Ophidian Eye
1 Leyline of Anticipation
1 Curiosity
1 Jace Beleren
1 Reverberate
1 Comet Storm
1 Seething Song
1 Banefire
1 Act of Treason
1 Reversal of Fortune
1 Browbeat
1 Worldfire
1 Curse of Bloodletting
1 Hypervolt Grasp
1 Furnace of Rath
1 Koth of the Hammer
1 Swerve
1 Electrolyze
1 Prophetic Bolt
1 Stitch in Time
1 Invoke the Firemind
1 Mirror Sheen
1 Quicksilver Dagger
1 Darksteel Ingot
1 Izzet Signet
1 Izzet Keyrune
1 Sol Ring
1 Rings of Brighthearth
1 Howling Mine
1 Font of Mythos
1 Spellbook
1 Venser's Journal
1 Vedalken Orrery
1 Sphinx-Bone Wand
1 Isochron Scepter
11 Mountain
1 Reliquary Tower
1 Nivix, Aerie of the Firemind
1 Magosi, the Waterveil
1 Valakut, the Molten Pinnacle
1 Coral Atoll
1 Dormant Volcano
1 Izzet Boilerworks
1 Desolate Lighthouse
1 Command Tower
1 Steam Vents
1 Izzet Guildgate
Niv-Mizzet, the Firemind works nice with all the whirlpool creatures, namely Whirlpool Rider, Whirlpool Drake and an awesome Whirlpool Warrior.