Spellheart Control

My first take:
Curve is super-low, though so are the lands. I would add in a multipurpose land or 4 and get the count up to 21-22. Desolate Lighthouse seems perfect. Mutavault, Faerie Conclave, and Ghitu Encampment give you extra dudes in a pinch. They also interact very will with Hour of Need (below) when you are mana flooded. Since your curve is low and you want both colors early, I would try to add in Steam Vents and Temple of Epiphany (if you have them) and/or their ilk. Shivan Reef and Mana Confluence might work, but you are probably paying the life every time you tap them. At the very least, I would add in some Terramorphic Expanses or Evolving Wilds. They fix your mana and filter your library.
You have a glut of both draw and spot removal and could use another finisher or two. I would look to replace the Telling Times and Hands of Bindings. Hour of Need is super-powerful in upgrading your (effectively) mana dorks in the late game.
Flashback and filtering spells that put cards in your graveyard work really well with the Chimeras. On the flashback side, I'm looking at cards like Deep Analysis, Shattered Perception, Think Twice, and Faithless Looting as upgrades for Telling Time and Peer Through Thoughts. Something like Forbidden Alchemy is exactly what this deck wants, even without the mana to Flashback. You might also consider a Mystic Retrieval or two to get back your good stuff. Casting and Flashbacking a Reckless Charge on a Chimera is probably gg.