Wheel pant fasteners, check with allen wrenches and make sure they are seated in threads and not just feeling tight.

Slip / Skid ball adjustment (mine got off grossly by delivery)

Seats for cracks, try to bend top forward to see if cracked where seat meets bulkhead if rear strap does not have tension.

Rear seat straps need tension.

Learn how to adjust throttle / choke friction and have tools with you. It's not really safe to fly when loose and can go loose when least expected.

Check functionality of avionics, (I still have no audio out on my garmin 396)

Confirm accuracy of sight gauge numbers by using dipstick, they might suggest that you have a little more fuel than you actually do.

Check cockpit light and gauge lights. and all external lights, including which switches turn them off and on and how they are labeled.

Check all switches and their labels.

Learn what kind of oil is installed and get a spare quart for servicing.

Test transponder functionality.

Test all weather / terrain displays and alerts video and audio.

Test if avionics should pass along comm and or nav frequencies.

Test to see if auto pilot can fly flight plan from other radio if this is an expected feature.

Check quality of composite and paint.

Check quality of windows.

Ask for samples of composiclean

Check heater

Check carb heat