I used a peep only setup on my old bow for years and had similar problems, although I attributed it more to "buck fever" then low light. This spring I got a new Tribute and changed my anchor point, so I added a eliminator button as a kisser just to help me find my new anchor point.

It's a great combination cause now I can draw with my eyes closed and when I feel that kisser I can open my eyes and my peep is where it's supposed to be. I also increased the diameter using the G5 Meta at 1/4" so I would have as much light transmission as possible. Right now I would say if I can't see it - then it's too dark to shoot!