Out of the Pit

So here is another image of my OC, Roseate Grimsbane. 

While I'm not too sure I like what lighting I did with the tentacles, I thought I would post this and perhaps receive some advice from you all. One of the things I have recently been using for shadows and lighting has been creating a completely dark layer with a low opacity and then using an eraser to parts of that layer for the lighting. 

Perhaps you have some advice on how to improve this in which case that will be great. I already have ideas for a different version of this image that I will be making in the future. 

---

Roseate Grimsbane belongs to me. 

MLP belongs to Hasbro.