If I were you and I had the chance to build my entire arsenal with 5 Motiv pieces, this is what I would do:
HEAVY OIL: Motiv Jackal Ghost. Strong read in the mids, early, smooth and continuous downlane.
MEDIUM/HEAVY OIL: Trident Quest. Clean, angular ball that will help me create shape down the lane.
MEDIUM OIL: Forza SS. Benchmark ball, smooth, predictable and a versatile ball to use on a wide variety of conditions.
MEDIUM/LIGHT OIL: Venom Shock. Great step down from the SS, and great all around ball.
MEDIUM/LIGHT OIL: Octane Carbon. Great step down from the Trident Quest, similar shape, weaker overall.