First of all, cool deck. Sigarda is a badass. And now I have a bunch of suggestions - Incoming Book of unsolicited thoughts & advice!

It looks like you've primarily opted for the enchantment route so far so let's start there...

Onto creatures that help with your enchantress gameplan:

Tutors! I hear these are pretty good, heh: Enlightened Tutor + Idyllic Tutor

A couple more spells that help your gameplan: Replenish, Retether and a new one that segues into my next main suggestion, the equipment route!: Open the Armory (bonus points for being from the new set)

Have you thought about chucking a few of the swords in here for funsies? I see you have 1 sword already + Stonehewer Giant so it looks like a little sub-strategy. Here's a list of the main ones for reference:

A couple of key supporting players: Puresteel Paladin + Stoneforge Mystic

Ok. I know that's a lot, especially when the deck is still so fresh and you're still thinking of your main gameplan. Also, I'm aware that this doesn't exactly help with trimming your deck down at all. With that in mind, here's a few cards that I think you could probably do away with...

Flickerform (clunky and slow in my experience...do you want to keep 4 mana back all the time?), Ghostly Prison (go aggressive instead!), Hyena Umbra (meh), Journey to Nowhere (Oblivion Ring + it's ilk are superior IMO), Sigil of the Empty Throne (awesome in theory, win-more in practice), Snake Umbra (also meh + the deck has no shortage of card draw), Spectra Ward (the pro effect means you can't cast further auras on Sigarda which seems prohibitive), Utopia Sprawl (meh), Avacyn's Pilgrim (meh), Bastion Protector (probably too fragile...Avacyn, Angel of Hope is the way to go if your wallet says that's ok), Containment Priest (apart from being good-stuff, maybe you have this in here for reasons I can't see?), Courser of Kruphix (Oracle of Mul Daya > CoK), Qasali Pridemage (decent but if you're having a tough time deciding on cuts I'd probably put this guy on the chopping block), Sakura-Tribe Elder (Steve is good but again, possibly cut-worthy - I'd go with a standard ramp spell like Kodama's Reach instead), Selesnya Signet (I've never liked the signets...I don't see a Sol Ring in here yet dammit!), End Hostilities (may hurt your own gameplan should you throw in more equipment), and Oblation (this was better pre-tuck rule, but the advantage you're giving an opponent is a tough pill to swallow).

Ok, book complete. I'm sure you've thought of most of these already but hopefully there's a few ideas in here that you may have initially overlooked. Enjoy the new deck brew sir!

Dude! Thanks for all the notes Forkbeard! I just started brewing this yesterday and haven't yet had a chance to dig through all my cards (hence no Sol Ring... yet). Definitely some awesome suggestions though, thanks!

Tonight I'm planning to comb through the rest of my cards to add the likes of Sage's Reverie, Trailblazer's Boots, Path to Exile, Aura of Silence, Stasis Snare (maybe), Acidic Slime, Day of Judgment, Swiftfoot Boots, Krosan Grip, Reliquary Tower and Temple of the False God.

Also, I super appreciate the comments on what to cut. Some of those I totally had an eye on to remove already (eg. I knew End Hostilities was poor for this deck and Oblation would be removed in favour of better wipe + other enchantment-based single target removal). Shockingly, I'm all out of Kodama's Reach! Heck, my very last Cultivate went into this deck. Those basic ramp staples sure see a lot of use.

Courser of Kruphix will be replaced by Oracle of Mul Daya... someday. When money allows for it. That's an upgrade that could likely wait until I've picked up some of the other high-power enchantments or tutors.

Tutors! Yes, there are many tutors I need to get. That'll be a budgetary limitation while I slowly acquire them all. But definitely needed.

So I added everything you suggested to my maybeboard. I'll start trading away precious family heirlooms to afford them all ;)