Hey, what you have so far is a strong start at upgrading the precon for your first deck, nice Hammer of Nazahn upgrade.

Currently you need to cut 24 cards to get to 100 cards. Some advice is start with cutting some lands because 43 lands is too much. Reduce it to 36 and if you think you need more mana then add more low converted mana cost (CMC) ramp sources or draw sources instead of lands.

Some lands to consider cutting:

• Vivid Creek
• Thriving Grove
• Thriving Heath
• Thriving Isle
• Azorius Chancery
• Simic Growth Chamber

All these lands always enter the battlefield (ETB) tapped and you have other lands that always do this too, but those other lands are better than these.

The next cuts to consider are some high CMC cards to reduce the mana curve.

• Valiant Endeavor
• Ironscale Hydra
• Realm-Cloaked Giant
• Resolute Archangel
• Dragon Throne of Tarkir

Further cuts are some cards that are not as good as others here or have similar or the same effects.

• Battle for Bretagard
• Fall of the Impostor
• Heirloom Blade
• Reflections of Littjara
• Skyclave Cleric  ^Flip
• Captain's Claws
• Conclave Tribunal
• Moonsilver Spear
• Shielding Plax
• Tangled Florahedron  ^Flip
• Suppression Field

Heirloom Blade and Reflections of Littjara are tribal cards that care about only one type of creature. That's not the strategy here since you have many different creature types. Skyclave Cleric  ^Flip and Tangled Florahedron  ^Flip are double face cards (DFC) that can be lands or played as the front face of the card and that can be helpful. The problem is the front face of the card is not worth playing even though they might be lands. Bala Ged Recovery  ^Flip is an example of a good DFC upgrade since front face is a good card and the bonus is that could be a land.

Suppression Field is a powerful card, but it affects equipment equip costs since that's an activated ability. Even if you control Puresteel Paladin with metalcraft activated you still have to pay 2 mana to equip the equipment to a creature you control. Puresteel will reduce the equip cost to 0, but then Field makes you pay an additional 2 mana to activate the equip ability. If an equipment is in your hand and you cast it or already on the battlefield you can't free equip if you control Field.

You have ways to get around having to pay for equip with attach. Difference is you're not equipping when you attach an equipment to a creature you control. The key word here is attach which bypasses the need to activate equip. You can free attach an equipment with Galea, Kindler of Hope, Halvar, God of Battle  ^Flip or Hammer of Nazahn. With Galea only if you cast an equipment from the top of your library, with Halvar only if the equipment is already equipped to another creature you control and with Hammer only if you cast the equipment or the equipment ETB. Free attach has synergy with Suppression Field, but the interaction is limited.

Good luck with your deck.