An interesting format, to say the least. Some first thoughts:
Library of Alexandria - Broken, unrestricted. Bad mistake for a "cheap" format. Crop Rotation is a common, too.
Sol Ring - Overpowered. Especially in fours.
Channel - Only non-broken because of Sligh.
Maze of Ith - Very powerful in a creature format. If I remember correctly, it was a C1 in Dark. Does C1 count as uncommon?
Zuran Orb - May not be completely broken without Balance...
All in all, I'd expect to see almost all decks except the fastest weenies use either four Libraries or four Sol Rings. A big critter green deck could concievably use 4 Rings, one Library and 4 Crop Rotations to have both broken card advantage and broken mana acceleration.
Defense / control has some interesting tools, but no blanket defense except Circles of Protection. Blue-White defense decks could work, but are impossible to build without knowing the metagame. Draw-Go with four Libraries, AccuKnowledge and Merchant Scroll would seem powerful, but it needs a way to clear the table. Well, someone will find a way to break it; they always do.


A couple decks to test:
Sligh, fairly close to a T1 version. Very, very fast. It loses some of the staple creatures and the Wheel of Fortune, but nothing else. Gains three Strip Mines to make up for it.
16 Mountain
4 Strip Mine (Worth the uncommon slots; cheap harassment is great for this deck)
4 Goblin Patrol
4 Mogg Fanatic
4 Raging Goblin
4 Mogg Flunky
1 Jackal Pup
4 Fireblast
4 Incinerate
4 Lightning Bolt
4 Chain Lightning
4 Goblin Grenade
3 Reckless Abandon


A black weenie, with a powerful card advantage engine. May be overwhelmed before the card advantage kicks in; might benefit from some bigger creatures + Pestilence.
4 Hymn to Tourach
4 Library of Alexandria
(Card advantage)

4 Sinkhole
4 Duress
(Random disruption, powerful with dard drawing)
4 Carnophage
4 Dauthi Slayer
4 Dauthi Horror
4 Skittering Skirge
(Cheap, powerful evasion creatures)
4 Snuff Out
4 Vendetta
(Defense chosen over more creatures, to buy time for the card advantage)
1 Demonic Tutor
19 Swamp


An attempt to abuse the broken Library. Main problem is the offense part; how to kill in the long run while still surviving to abuse the card drawing? Perhaps more mana acceleration would help.
4 Library of Alexandria
4 Crop Rotation
(8, Drawing engine)
10 Forest
10 Mountain
(20, Basic land)
4 Lightning Bolt
4 Incinerate
4 Fireball
4 Ghitu Slinger
1 Maze of Ith
(17, defense)
3 Yavimaya Wurm (Big, mean)
4 Blastoderm    (Huge in this format)
4 River Boa     (Regenerates, efficient)
4 Llanowar Elves (Acceleration)
(15, offense)
Yours truly,