I would use
Lingering Souls instead of
Midnight Haunting because the flashback ability is important. Decks that run hand disruption like Jund or
Waste Not could take
Midnight Haunting and you would not be able to use it. Granted you have other means of token generation such as
Raise the Alarm. Also if you have
Polymorph or
Proteus Staff, they would rather Thoughtsieze or
Inquisition of Kozilek that. To be able to use
Lingering Souls flashback ability you could splash black with
Arcane Sanctum and/or
Mana Confluence.
Also, man-lands might not be a bad idea. If price is not a problem you could use
Inkmoth Nexus.
Blinkmoth Nexus also. If colored mana is a problem you could use
Faerie Conclave and/or
Forbidding Watchtower. They can also
serve as emergency blockers if you do not have any token generators in hand.
For the sideboard, I would recommend cutting 2
Lightning Greaves for
Leyline of Sanctity. If you have it in your opening hand you are immune to hand disruption as well as burn spells.