Ramp and amplify. Bastion Garrison in conjunction with amplification can enable the generation of a lot of units, although I'm not sure if it'd be better off in the market. Speaking Circle simply seems to be a good site - I just about always get at least 1 good spell from it for the turn I play it. Martial Efficiency has been really handy - even with no Bastion garrisons in play (but bloody amazing when there is!).
So far I've got to Diamond 3 (at the end of last season) with this deck and I believe it can go further.
Builder's Decree
x4
1
Logistics Expert
x4
2
Desert Alchemist
x4
2
Martial Efficiency
x3
3
Winchest Merchant
x4
4
Bastion Garrison
x4
4
Diana, Faith's Shield
x3
4
Enter the Monastery
x4
4
Maddening Whisper
x2
4
Onoris Roa
x3
5
Moonstone Vanguard
x4
6
Sabre of Progress
x2
6
The Speaking Circle
x3
6
Touvon, Skybreak Giant
x4
8
From the Heavens
x2
Justice Sigil
x9
Time Sigil
x8
Combrei Painting
x4
Seat of Progress
x4
View Deck on Shiftstoned
Martial Efficiency has been very powerful with a Bastion Garrison in play. Spawning a bunch of 3/2s (at least) at fast speed whilst reducing enemy attack values often leads to victory. I've only been playing this deck in silver and gold so far mind you - not quite diamond YET.