In general, your deck is lacking focus. With a commander like Surrak, all you really need to focus on is making lots of mana, playing big, threatening creatures and making sure they actually deal damage (e.g., run lots haste enablers). A lot of your creatures simply aren't big or impactful enough.
1 Surrak Dragonclaw
Creatures
1 Chaos Imps
1 Clever Impersonator
1 Dack's Duplicate
1 Elvish Mystic
1 Embodiment of Spring
1 Heir of the Wilds
1 Hellkite Charger
1 Heroes' Bane
1 Horizon Chimera
1 Huntmaster of the Fells
1 Joiner Adept
1 Llanowar Elves
1 Master Biomancer
1 Mercurial Chemister
1 Mindwrack Liege
1 Mogg Sentry
1 Murkfiend Liege
1 Prophet of Kruphix
1 Rattleclaw Mystic
1 Reclamation Sage
1 Reef Worm
1 Ruric Thar, the Unbowed
1 Sagu Mauler
1 Savage Knuckleblade
1 Solemn Simulacrum
1 Steel Hellkite
1 Stonebrow, Krosan Hero
1 Stormbreath Dragon
1 Vorel of the Hull Clade
1 Willbender
1 Wolfbriar Elemental
1 Yasova Dragonclaw
1 Awaken the Bear
1 Cancel
1 Capsize
1 Cyclonic Rift
1 Destructive Revelry
1 Dissipate
1 Fog
1 Hinder
1 Mindswipe
1 Pongify
1 Stubborn Denial
1 Temur Charm
1 Trap Essence
Enchantments
1 Asceticism
1 Awakening Zone
1 Bear Umbra
1 Death's Presence
1 Temur Ascendancy
Sorceries
1 Anger of the Gods
1 Ranger's Path
1 Rite of Replication
1 Savage Punch
Land
11 Island
11 Mountain
11 Forest
1 Command Tower
1 Frontier Bivouac
1 Gruul Guildgate
1 Izzet Guildgate
1 Simic Guildgate
1 Rugged Highlands
1 Swiftwater Cliffs
1 Thornwood Falls
1 Sol Ring
1 Temur Banner
Planeswalkers
1 Domri Rade
1 Xenagos, the Reveler
Cuts:
Mogg Sentry (we don't have enough control over it)
Fog (we're trying to deal damage, not prevent it)
Destructive Revelry (worse than Hull Breach)
Ranger's Path (strictly worse than Skyshroud Claim)
Heir of the Wilds (not sure what this is supposed to achieve)
Vorel of the Hull Clade (we don't have enough ways to put +1/+1 counters on our creatures)
Horizon Chimera (we're not playing life gain)
Elvish Mystic, Llanowar Elves (mana artifacts are less vulnerable, plus they don't have summoning sickness)
Savage Knuckleblade (the "once per turn" clause on his pump ability means he doesn't hit hard enough for EDH)
Mercurial Chemister (costs 5 mana and can't use trample effectively)
Adds/Considerations:
Hull Breach
Vithian Renegades
Overwhelming Stampede
Skyshroud Claim
Kodama's Reach
Gruul Signet
Simic Signet
Izzet Signet
Acidic Slime
Ogre Battledriver
Explosive Vegetation
Urban Exploration
Hydra Omnivore
Krosan Cloudscaper
Cultivate
Farhaven Elf
Fierce Empath
Maelstrom Wanderer
Shipbreaker Kraken
Spearbreaker Behemoth
Anger
Genesis