The best drivetrain is the the one that fits your team's capabilities.
Each drivetrain has pros and cons, so it's best to choose the one that your team is most capable of producing. This should take into account design, manufacturing, assembly, repair, and control.
I'd look into decision matrices, and use those to help you decide which is best for you and your team.
Edit:
Here's a sample decision matrix for a drivetrains.