Rate my deck please. Magic the Gathering?

With ramp decks, you will want to have at least 21-24 land. You are, with your current set, going to be drawing too many big cards too early. I recommend taking out a few of the Eldrazi derivatives, which is stuff that has an Eldrazi's name, but isn't actually an Eldrazi. I also recommend obataining three or four Khalni Heart Expeditions, as they work wonders, and a three or four Valakut, the Molten Pinnacle. This will allow you to bring out land very quickly, and with Valakut out, it will permit you to deal large amounts of damage quite quickly. You can NEVER go wrong with a tactic that let's you deal damage for merely putting out land! Hope I helped.