Hey there rumple76 . Great question. I know what you mean.... the blade on the Versa tool is a triangular shape. So the deeper you push it in, the longer the cut line will be.
A more ideal shape would be blade that looks something like this:
Not sure if my mockup would be strong enough, but something at least close to this would be better. I haven't see any blades like this anywhere. I just searched the Walnut Hallow
website and couldn't come up with anything either. Maybe we should get in touch with them to recommend this product addition?
If you have any metal cutting/grinding tools, you could probably modify the blades yourself. But an easily available commercial part would be nice.
In any case, you can still cut just about any pattern with the regular triangular blade. My main advice would be to only push the blade in as far as necessary to cut through to the inside. Take note of the of the foam thickness, and try to go that deep with your blade.
In areas where the pattern detail is even tighter than the blade width allows, you really have no choice but to cut a line that goes a bit longer than what's in the design. These "over-cuts" won't really show up, since the foam (on Gemmy / Michaels pumpkins) is a bit spongy, so it tends to close back up, hiding cut lines.
If you do cut beyond the line of the design, just be carveful that you're not cutting into a thin connecting piece that is meant to be pumpkin that remains. You don't want to accidentally cut off any pieces.