Some say it's incoherent, but it's really just a very conceptual thinker
Compared to Set Boosters, which are now replaced by Play Boosters, the latter have one less non-foil Wildcard slot, but Wizards said that the overall pull value remains the same
Jetmir, Nexus of Revels says the more the merrier, providing cascading board pumps depending on how many creatures you control
Each guild has it's own signet which produces the appropriate colors and every single one is a Cube staple
Dowsing Dagger: Another hoop-jumper to get where you want to go, its likely worth the effort, especially given that it costs one less mana than Gilded Lotus (two to cast, two to equip) and is less vulnerable once its a mana-producer
And, perhaps most importantly, always aim to build something you'll actually enjoy playing