That is an amazing idea to use ink blockers even for one color. I put on a ton of ink and it ended up just smushing all over the place. I will definitely give that a try next time I print. I printed on wool felt. I also tried on quilitng weight cotton, which worked a little better. But, I want to use wool felt for this design since I'm going to make him (aka Kevin the Monster) into a softie.
I printed again today and used more ink than yesterday. His back definitely turned out better than his front.