I also added a slight shadowing on each section edge of the pumpkin with brown fabric marker. I still need to sew down all the leaves and the pumpkin and I'm leaning towards the invisible thread again. Since this has so many light colors, it should work well. Here's all the leaves with veins added.
Don't mind the mess of threads, I always leave a mess and then pull them through to the back using an easy threading needle. You know the kind that has an open top and you just pull the thread on the top to thread the needle. This works fast to pull all the threads to the back and then I knot and clip them. This is not the best photo but you can kinda see the veins sewn in.