Just my personal opinion. I have flashing head and tail lights. I only ride in daylight. I omit the head light when riding very low traffic back roads mainly because I have only one headlight that isn't randomly shut off by my Garmin computer. Always a high visibility vest or windbreaker. I like my Thousand brand helmet. I have a mirror on all my bikes. Can't use a helmet mirror because of near vision issues. I'm not interested in the radar units. That might change if silent Ecars become a regular thing.
I agree with Delbiker1. No guarantees when riding in proximity to cars. I ride defensively and obey all the traffic laws, prefer my back country gravel riding but accept that there is a risk every time I'm riding.