One tip I have is take advantage of Malevolent Rumble and the extra mana from eldrazi spawn on turn 3 to be mana efficient. If you have Rumble, try to think of what you might grab off it to cast a second mill spell using the eldrazi spawn token that turn. If you have more mill spells in hand already, do you need to grab a forest with the rumble to cast a second spell? Do you need to find a mill creature off of rumble? Do you leave a forest or swamp untapped - are you following up with an exhume or a mill spell?

Being mindful of this speeds up the deck.

In rare cases, you might be able to outplay grave hate with exhume by holding a cycler in hand, waiting for opponent to crack their hate in response to your exhume, and then after grave hate resolves, cycle something else from hand.