Well first of all, the lighting should be coming from the center, and you made it look like it's coming from like the right corner of the pumpkin. Second, the light on the inside is too similar to the color of the pumpkin which makes it look weird.
I suggest you take the normal jakolantern and draw a candle in its mouth with light around it (fainter than the one you have now, so that you can still see some black on the outer edges) and then make some highlights around the eyes and mouth of the pumpkin so that it looks like the light is coming out of it.
Dude..this Texture pack is sweet. I know it contains heaps of textures from the default and other packs. but the ways in which you have changed them, works Perfectly!! Great work. and ill be looking forward to any other content from you in the future!!!