Emphasize the core elements of each color - Each color will be heavily focused on it's own unique identity. I want it to feel almost like an RPG where each color is a class that has it's own distinct spells that separates them from the other colors. If you're playing against a blue deck, you should expect them to have some card draw or counterspells. On the other hand if you are playing against a gruul deck, you won't have to worry about any graveyard shenanigans, as that is mostly reserved for Black. The color pie is the driving factor in what gets included in this cube. Though it has changed over time, many of the core elements have remained. The multi- color decks will develop their own themes naturally.
Use slightly lower powered cards - I'm not taking the strongest version of any effect based purely on it's power level. If there is a slightly worse version of a card that I think plays better or fits more thematically, then I would have no problem using it. This expands the options of cards I can include when I don't have to use the strongest version of every slot. It also reduces the overall cost of the cube.
Keep the mana curve low - This is to increase the number of game actions players can take each turn. Green is the only exception to this rule. I still wanted green to have some ramp but to have the ramp targets not be autowins.
Keep drafting open - There are no "archetypes". Instead I wanted to just focus on aggro, control, and midrange and let it expand from there. There are no infinite combos. There will still be some cards that change the direction of your draft in an interesting way.
For the sake of readability and visual cohesion I am constraining myself to a very specific card frame/layout. It must be the 2015 frame and if it has flavor text it must have the separating line. For example, the difference between these two.
Exceptions being the basic lands and Cogwork Librarian. This is definitely a bit extra but I enjoy the consistency and I believe it helps new players at the same time.White is a color that can range from Aggro to Control and anything in between. While a mono-white deck may become a midrange pile, it will be a great pairing with any color for a deck of any speed.
Go-wide creatures: Resolute Reinforcements, Usher of the Fallen
Artifact/Enchantment based removal: Portable Hole, Touch the Spirit Realm
Protection: Dauntless Bodyguard, Gods Willing
Evasion: Faerie Guidemother, Ardenvale Tactician
Equipment: Ancestral Blade, Maul of the Skyclaves
Conditional Wrath: Cataclysmic Gearhulk
Blue is the color of Control. It can be a great asset to a midrange plan with big card draws or even join with Red for a possible controlled burn...
Counterspells: Counterspell, Mana Leak
Card draw: Hieroglyphic Illumination, Treasure Cruise
Bounce spells: Fading Hope, Into the Roil
Spells Matters: Snapcaster Mage, Haughty Djinn
Efficiency at the cost of life. While Blue controls through counterspells and bounces, Black controls through destroying creatures and forced discards. The graveyard is essentially a second hand for black and will almost always be utilizing it for additional value. Black can also splash into aggro decks and midrange.
Reanimation: Reanimate, Unearth
Forced Discard: Duress, Dread Fugue
Creature Destruction: Cut Down, Bone Shards
Life Cost: Infernal Grasp, Thoughtseize
Red is the most straightforward color as the color of aggression. Whether through Burn spells or hasty creatures, red is trying to kill the opponent as fast as possible.
Burn: Lightning Bolt, Play with Fire
Aggressive Creatures: Ragavan, Nimble Pilferer, Rabbit Battery
Bulky Midrange Threats: Death-Greeter's Champion, Shivan Devastator
Combat Tricks: Blazing Crescendo, Embercleave
The iconic strategy of Green is ramp, which I have strongly supported here. This will typically be used to get a 4-5 mana value creature out a turn early with a couple options to ramp out a 6-7 drop. Combined with a control color, decks can survive to the late game to win with the big green creatures. Though green may not be the most aggressive deck, it can join with an aggressive color to form a fast midrange deck. Green is also the color to enable multi-color/5-color piles.
Ramp: Llanowar Elves, Arbor Elf
Big Creatures: Ancient Imperiosaur, Territorial Allosaurus
5-color Enabling: Utopia Sprawl, Birds of Paradise
Midrange Value: Jewel Thief, Tireless Tracker