I'm not sure it's possible to gauge the relative difficulty of the two tasks, since they're equally impossible for me. I take it healing the blind is easy for you?
Jesus in fact pointed out that sometimes people misjudge what's harder. When confronted with a paralyzed man, he first told him, "Your sins are forgiven." After someone challenged his ability to do that, he pointed out it was easier than telling the man to get up and walk (which he then did, also).