Sharp points can be a challenge. I do mostly fused applique with Wonder Under because I like the exact shapes you get. I have used the method where you sew the shape outline to a thin piece of fabric or interfacing and turn right side out through a cut opening. This works for me if I just want a shape to hand stitch down. I use a used dryer fabric softener sheet for the light weight back. I sew around the shape, clip any curves of inside/outside corners and cut a slit in the dryer sheet and carefully turn right side out. Try it on a simple heart shape and see if it will work for you.