is it risky if HDL is too low?

This simple question is more complicated than meets they eye. HDL is known as the "good cholesterol" and is often considered to relate to the mechanism by which cholesterol is removed from arterial sites. Generally physicians pay more attention to lowering the LDL (the undesirable cholesterol), but more attention has been paid more recently to raising the HDL level.
The niacin group of drugs will raise HDL.
I think it would be wise to have your physician assess your general health, family history, occupation, habits, blood pressure, cardiac status, etc in order to make the decision about treating you to raise your HDL level.

Your HDL might be perfect for your individual body. Seek a "functional" medicine practitioner. If you are worried about disease risk, assess inflammation. Homocysteine and C-reactive protein tests. 50% of people who had heart attacks had normal cholesterol levels. Simply looking at cholesterol "standard" panels are many times useless or very preliminary testing.

ewbeyond, it sure is good to have you around.