I too was wondering about the hesitation for night flight. It's good you have established your personal mins. Even better is to stick to them. Yet I believe you need to push the envelope, by avoiding the night you are depriving yourself of some fantastic opportunities.
I love night flying and consequently I have lots of night time. Smoother air, increased vis, far less traffic, ATC not so busy and ready to shoot the **** with you or handle the odd request; all are benefits of night flying compared to day.
As for engine out at night, it's really a head game you're playing. That is, unless you have the auto rough option on your engine. Just go out and build some competency.
I do have one personal min I try to stick to WRT night: no single engine over mtn terrain at night. However, I have a margin if I'm familiar with the immediate terrain and would like continue in that case.
Now that I think about it, passing PHX heading east a couple months ago was at night in MVFR. We picked up some light rime and while that certainly got our attention in no way did I feel uncomfortable because I knew that portion of the route pretty well and had lots of options open in case it got worse.
So, I guess it all comes down to options. Day, night, VMC, MVFR, IMC, makes no difference as long as you identify your options and keep evolving them as the flight progressess. Hey, I just had an insight.