C2 is probably not needed at the low frequency you plan. A value of 10 nF (0.01 µF) is more typical when it is used and is recommended in the datasheet.
As for the MCU power, I assume you are referring to R3,R4, C3, C4, and D3. That design is to decouple the MCU from glitches produced by the motor and solenoid. Think of a low pass filter. You will need to include decoupling too, but it is understandable that you left it out for simulation.
Are you sure of the orientation of D1 and D2?
John