Sure, Invasion of the Giants has aggressive components, but both Glimpse the Cosmos and Battle of Frost and Fire are better in a slower deck, and Beanstalk Giant isnt the worlds most aggressively costed creature either
What matters most is clarity
Enlightened Tutor may get you an enchantment or artifact for a single mana, but you lose a card (the tutor), and you still need to cast said enchantment or artifact
Both of these feature absolutely stunning artworks that play into the decks theme, but the magical feeling of finding out whats the final secret card of a year-long delayed product was, for many players, met with disappointment
I dont expect you to copy my method step by step - I just hope seeing how someone else does it might incentivise you to finally tackle the hurdle that is sorting and maintaining a collection of Magic cards, and hope to provide you with some tips and tricks