The exchange of life for cards has been a stalwart since Legends and its a pretty good way to make these cards feel different from their blue (and sometimes green) counterparts
Until a player planeswalks, all lands that player controls are Islands
(Food is an artifact with " , , Sacrifice this token: You gain 3 life." Treasure is an artifact with " , Sacrifice this token: Add one mana of any color.") Creature - Elf Scout Color tag templates(None) Treebeard, Gracious Host Trample, ward When Treebeard enters, create two Food tokens
See the full list in the Similar cards section above.
As far as changes to make to the budget build of the deck, I'm not sure there is really much to change that doesn't increase the budget
The deck does an impressive job of making WUBRG feel smooth rather than clunky