chassis to board gnd isolation
C16/R56 packages and voltage should be changed to meet the 500V isolation requested by VITA57 standard:
Rule 3.20: Boards shall provide a minimum of 500Vdc and 1 MΩ of isolation between the FMC front panel bezel and the mezzanine circuit ground.
C16 is 50V/0402 R56 is 0402 and should be at least 0805