I think you are close,
As stated in #1, remove the purple wires. Adding the 10K (could be 50k) to ground makes sure the MosFet is off if the arduino is not connected, but is not required for functionality. But it is a good idea.
Regarding the series gate resistors and the motor diodes. The choices depend on whether or not you are PWM'ing the MosFet's and at what frequency.