Darlington array (ULN2003) to N-Channel MOSFET (RFP30N06LE)

It's a good idea to add decoupling on the Vin - voltage regulator specs usually specify an input-side decoupling capacitor as well as output side.

What current will the MOSFETs have to carry? - those MOSFETs will need heatsinking above 2 or 3 amps.