I tried keeping the rares to the bare minimum in this build.
You totally do need merchants if you wanna play control + harsh rules. The 1x Chains in the market is really easy to obtain from the premade deck that you can buy from the in-game store.
The first cards you should build after finishing this build are Crests to swap with some of the sigils so you can scout. I would experiment with some Tamarys + hailstorm. Also try to get Vision of Austerity (from another campaign) for your market and also get Xulta Convoys so you can then include Sanctums.
Thanks for checking out the deck, if you wanna say hi you can always pop on stream at twitch.tv/bardeane!