I think this hand is super interesting. At first glance my gut reaction is, "Yeah, I'd keep that." but when you analyze the hand a bit more I think it's not as obvious.
After you've cast the pair of Thoughtseize your hand doesn't actually do a whole lot. Meaning your options are to draw a Dark Ritual or Lion's Eye Diamond and cast Ad Nauseam (Chrome Mox would imprint Empty the Warrens). The downside to this is you're likely somewhere between 10-14 life.
If you're up against a blue deck I would aim to Infernal Tutor for a second copy of Chrome Mox and then Empty the Warrens for around 8-10.
Something that is easy to forget is at this point you've had three to four draw steps and this hand has more than likely gotten better. Almost every card in the deck improves this hand as they improve one of the two game-plans. I think the only way it gets worse is if you draw consecutive land drops, but at that point, you need to acknowledge you made the right decision but weren't rewarded.
I can see why anyone would be skeptical on this seven, but I believe it to be a keep.