What things to check on road bike after a long trip on poor roads
I think road bikes are actually more durable than a lot of riders give them credit for. Unless you were seriously crashing into potholes there should not be any damage (although you may have picked up some paint dings from loose gravel surfaces).

You can do a standard 'once-over', paying particular attention to the wheels:


If the dirty or muddy give it a wash and clean and re-lube the drivetrain and chain
Check drive-train and brake functionality
look for rattles and anything loose
Check for play in headset bearings
Check the rims are true
Look for dings in the rim flanges and scratches in the braking surface.
Check there are no loose spokes.
Check for damage to tire tread or sidewalls