If you are wanting to combo off with your mana dorks I would try out Earthcraft before Concordant Crossroads. Also I have to respectfully disagree with your assessment of Azusa, Lost but Seeking and Exploration. This deck excels at using mana dorks and friends to put a ton of mana on the table by pulling it out of your library, not from your hand. Also dumping all the mana from your hand seems to me like it would make each Armageddon hit you harder than it needs to, and ramping back up to Armageddon mana again really quick seems a bit silly. I would be more concerned about having my Armageddon's resolve and hit a lot of lands a few turns later than casting it as soon as possible when my opponents most likely haven't recovered form the first one anyways.The only time is see you really wanting Exploration and Azusa, Lost but Seeking is when you draw Life from the Loam, and even then its only that great if you're picking up lands that do things.
Tukatongue Thallid, Scatter the Seeds, and Goblin Rally should get cut seeing as they don't have much impact on the board. I think you'll find that any sac outlet that requires mana to activate is quite frustrating (excepting Perilous Forays), and I could be wrong, but I am a little put off by Dark Prophecy seeing as you could accidentally kill yourself.
Serra Ascendant has been Errata'd to 50 or more life for commander, so something else to put in that spot might be better than a 1/1 with lifelink. Also Prime Time is banned too...
Forgive me if I'm wrong but I'm pretty sure Saffi Eriksdooter, Sun Titan, and a sac outlet are an infinte combo, and in my opinion, they are better stand alone cards than Reveillark and Karmic Guide.
-Mana Reflection: You're not playing a big mana deck
-Masked Admirers: Overcosted draw
-Exploration: You aren't playing a big mana deck
-Concordant Crossroads: Helps Opponents
-Academy Rector: To few sac outlets to make him a reliable tutor
-Pull From Eternity: Doesn't impact the board
-Yavimaya Elder: I don't know about you but I have always found him to be rather slow and underwhelming
-Golden Wish: Overcosted
-Global Ruin: Underwhelming, especially against decks playing multiple colors
-Magus of the Candelabra: You're not playing a big mana deck
-Khalni Heart Expedition: You're not playing a big mana deck
-Azusa, Lost but Seeking: You're not playing a big mana deck
Then as for more/better win conditions I would suggest either playing more combos:
Archangel of Thune+Kitchen Finks/Spike Feeder
Nim's Deathmantle+Ashnod's Altar
Melira, Sylvok Outcast+Persist Creatures
Or Primeval Bounty and Rampaging Baloths both have some pretty good synergy with your general, and both make your mana dorks better late game.
Tukatongue Thallid, Scatter the Seeds, and Goblin Rally should get cut seeing as they don't have much impact on the board. I think you'll find that any sac outlet that requires mana to activate is quite frustrating (excepting Perilous Forays), and I could be wrong, but I am a little put off by Dark Prophecy seeing as you could accidentally kill yourself.