Is EE part of the reason that you went down to 2 Paths in your last couple lists? I feel like we rarely see fewer than 4 Paths in any list, and would be interested to hear how that went in your testing.
Sabinfrost, I like the idea of Mentor as a wincon and will be interested to hear how it tests out. I like that you can choose "human" on Cavern so that Snap and Mentor are both counter-proof. I understand the appeal of G-Probes for 0 mana with Mentor, but would be concerned that they don't do much in multiples when Mentor isn't in play. My own inclination would be to swap some probes for Serum Visions, though of course I have no testing to back that up.
Sylvan Library
Chain Lightning
Mishra’s Factory
Elvish Spirit Guide
Fact or Fiction
Won't be in:
Gitaxian Probe
Scalding Tarn
Abrupt Decay
Thoughtseize
Snapcaster mage
Too bad,, but you're probably correct. It seems too much to hope for one more land starting with "A" before Ally Encampment...