Is phosphatidylserine a safe and worthwhile supplement to try to improve length and quality of sleep which is now 3 hours on average?

Possibly: Ps used to be derived from cow brains, so there was concern about transmitting infections. Now it is usually derived from plants. It has been studied and found to be safe up to 300 mg a day. Over that dose it may actually cause insomnia. It has not been studied for it's efficacy for insomnia. However, I have recommended it for patients who are very stressed and anxious and have had some success.