Beast Whisperer etc replacement

Hello all,

I am looking to lower the budget of my [[Ruby, Daring Tracker]] deck. This is a 2-4-7 build where you basically just play ramp + gruul stompy. T2 cast Ruby, T3 cast 4CMC ramp, T4+ you drop 6+CMC bombs.

Looking to see if anyone has good hidden gem replacements overall for my build. Also mainly looking to see if there are any cheaper 4CMC card draw spells akin to [[beast whisperer]] as that is a $10 card now.

Thinking of [[Vizier of the Menagerie]], is top deck and only creatures too narrow for my deck? Thanks

https://moxfield.com/decks/qv-eAX7uE3KgCDEvSaZ-4w

Any help is appreciated.