Guilty Conscience is not modern legal
I think you might have a problem against flying decks
maybe playing
Angelic Gift might help.
Against aggressive decks you might want to consider:
Pyroclasm (against a lot of creatures, obviously)
Lightning Helix,
Lightning Bolt (against single threats)
Boros Reckoner (very powerfull on turn 3-5 and gives you some creaturs on the field, also possible with your damagespells (13 damage --> 13 damage face))
Gilded Lotus is realy realy slow. you will never need the additional mana I think.
if you wanna play
Blasphemous Act, you only play it in the case he has alot of creatures
Shivan Meteor, cost 5 equal to the costs of your
stuffy doll --> you have 5 mana anyways
I think that
Etherium Sculptor will not bring enought value in your deck
in case you play against black, it is the only target of his destroy creature spells,
if you dont play him, his destroy spells are
dead cards in his hand.
Also you might have a problem against all the exil spells there are.
Playing
Hindering Light or
Negate helps against them.
hope that helps
best regards