Refined Pauper Cube

Archetypes: two per pair
UB: Control ; Tempo
UW: Fliers ; Artefacts
UG: Ramp ; Multicolour
UR: Non-creature spells
BW: Life gain ; Aggro
BG: Recursion
BR: Sacrifice
GR: Stompy ; Kicker
GW: Go-wide ; +1/+1 counters
RW: Aggro ; Equipment ; Heroic

These three colour wedges may also work, there's a lot of fixing in this cube
Esper: Control
Bant: +1/+1 counters
Temur: Ramp
Grixis: Tempo/control
Abzan: Reanimator?
Jeskai: Spells
Sultai: Ramp
Mardu: Aggro
Jund: Sacrifice
Naya: Aggro

Thought for the day: All limited decks are various shades of midrange...