It sounds like you have a pretty good handle on the issues now. Riding at night is probably an acquired taste, and the more you do it, the more comfortable and secure you will feel. It sounds like changing your work schedule is probably a good idea, all else being equal.
My impression is that you are currently into increasing both your physical fitness and your sense of "mastery" in the world? Have you considered a basic self-defense course? This might help accomplish both goals, fitness and self-confidence. These classes are also a lot of fun, and often awaken interest in more advanced martial arts training.
I love riding at night in my inner city area, but would be more reluctant in a rural or poorly lit suburban area, But that's just me and what I'm accustomed to. I do recognize that night riding is riskier in almost any area. I have worked 1500 - 2330 for many years and I love it, but obviously this is a minority opinion. I have enough seniority at the hospital to work days, but I doubt if I ever will. I love having my mornings free for long bike rides, and I have learned to love the commute home late at night.