These goodstuff decks make the high-cost creatures more playable because they are able to play them sooner, and because their density of powerful cards means they dont need any one threat to dig them out of a hole or win the game outright
Vivien's Grizzly is certainly costed as a common, but you can still make use of it in bear decks, or maybe with Agatha of the Vile Cauldron
Aether Revolt was overshadowed by the day-one errata for Felidar Sovereign and the ban for Smugglers Copter and Emrakul, the Promised End, Ixalan was bizarrely underpowered, and the supplementary sets were wearing thin, with Iconic Masters a particularly discouraging fizzle in the Masters line
They offer alternative costs and synergistic effects that can enhance your capability to draw cards
#8: Squall, SeeD Mercenary Squall has a simple ability that returns a permanent card with mana value three or less from your graveyard to the battlefield when it deals combat damage