Umm...that deck can't use it's Reverse Times OR it's Toadfish's skills.
I'm also not sure that quantum denial is the best route to take against Light. Not sure if it's bad, either, but just not sure that it's great.
Here are my thoughts about each matchup:
ItzSean -- vs

My suggestion:.
Mark of Life
8x Water Pillar
4x Life Pillar
5x Forest Spirit
2x Thorn Carapace
1x Druidic Staff*
2x Arctic Squid*
4x Congeal
4x Toadfish* (Yeah, you don't have the

to use their skill, but they're decent attackers.)
(If you don't have those rares, I'd replace the starred cards with)
1x Life Pillar
2x Nymph's Tears
4x Blue Crawler
---and if you're gonna go that route, and you have one, just straight add a Green Nymph.
Why: Light doesn't have creature control or permanent control, so your Squids and Dragons will do the job, and your Thorn Carapace will end RoL/Hope and any funky Angel tricks he might try. Forest Spirits will outgrow both Hope and Miracle.
Alternately, if you're worried about a simple rush, swap Thorn Carapace for Ice Shield. Works either way.
The dictator -- vs.

Mark of Air
8x Water Pillar
5x Air Pillar
2x Thunderstorm
2x Eagle's Eye*
1x Flying Weapon
2x Toadfish
2x Ice Shield
4x Ice Dragon
4x Ice Bolt
Why: Aether has a lot of threats it can field, and you need to be ready for RoL/Hope (Thunderstorm, Toadfish), Fractal Pests (Toadfish, EE, 2xThunderstorm), and a simple mono-Aether beatstick with Phase Shields up the wazoo (Ice Shield, Ice Bolt.) It's not ideal for any one of them, but it should be able to go head to head with each.
If you don't have 2 Eagle Eyes, ditch the Flying Weapon as well, and I suggest 2 more Ice Bolts and a Short Sword.
Essence and Kael Hate -- vs.

Entropy, in this format, loses one of it's biggest assets (true rainbow play), but it can still field surprising threats. Butterfly Effect and Maxwell's Demon are both nasty if you have no creature control, and Discord can ruin your day if you're not ready for it.
For Essence:
Mark of Aether
10x Sapphire Pillar
5x Aether Pillar
3x Arctic Octopus
2x Abyss Crawler
2x Mind Flayer
1x Nymph's Tears
1x Ice Shield
3x Quintessence
2x Fractal
1x Electrocutor
Why: All creatures are Paradox-proof. Quintessence will make an Arctic Octopus able to hold down 4 critters without any likely response. Fractal will work around Antimatter. Mind Flayer+Electrocutor will disable any mutant skills and/or Purple Nymphs.
For Kael Hate:
Mark of Death
8x Sapphire Pillar
5x Bone Pillar
6x Poison
2x Arsenic
5x Chrysora
2x Arctic Squid
2x Ice Shield
Why: An all-poison offense negates Antimatter, no creatures vulnerable to Maxwell's Demon, Arctic Squid should be able to keep Butterfly Effect from killing your shield, poison bypasses Dissipation Field. Really, as long as they don't splash mad creature control, this should be a cake walk.
Levgre -- vs.

Mark of Aether
15x Water Pillar
2x Quintessence
6x Ice Dragon
4x Arctic Squid
3x Mind Flayer
Why: Darkness has Steal (no Permanents in your deck), Pests (you need repeatable creature control), and Vampires (You need to keep them from attacking you.) It lacks large-scale creature control, fortunately. Here's a deck that should work as long as he doesn't go Fractal Pests.
This deck gives you LOTS of quanta to use all of those Squids, Flayers to eliminate Vampirism, Squids to shut down Pests and attackers, and nice sturdy Ice Dragons to survive Drain Lifes.
Harakirinosaru -- vs.

Big threats are Graboids and Earthquakes, but really a prepared Water deck should be able to handle that on it's own terms. I'm not that familiar with Earth/X duo decks besides Lava Golems and Pests, but this deck can handle those, too.
Mark of Air
14x Water Pillar
2x Air Pillar
6x Toadfish
4x Ice Bolt
2x Arctic Squid
4x Shockwave
Why: Graboid Rushes and Lava Golems both require fast and firm creature removal, and other Earth creatures (or Golems that have over-Grown) are big and hard to kill -- thus, Shockwave which fills both roles (with a Squid out). If they have EQ or Pests, the mass of pillars will help -- if not, they'll help build Ice Bolt to the point where you can get in a killshot with them. There's no permanents in case they run Gravity for Pulvys -- the kill is slow, but unless they go with a Lava Golem deck with mad creature removal, I don't see it being too few creatures to be able to win.
Feel free to ignore, modify, or use my suggestions. That's just what I think will give each of us the best chance of winning with what we got.
