Considering that exiling things is pretty easy to do nowadays, Ketramose can easily turn into a card advantage engine
There is definitely room for improvement, and I would argue you could go even lighter on the creatures, taking out some unnecessary ramp or even removing the Monarch mechanic entirely, and instead going with some additional enchantments or spells to really apply the pressure to your opponents
Autochthon Wurm is the underappreciated fifteen-drop in Magic , and it deserves some love too
Put the exiled cards on the bottom in a random order.) Rebound (If you cast this spell from your hand, exile it as it resolves
It is not all upside, by using the enchantment ramp over creatures you lose some consistency on your Overrun kills via Garruk and Craterhoof which are your main routes to victory
If the exiled permanent was a commander, the tokens won't be commanders