In essense, he's saying. If it's too easy to do it, find a way to make it harder.

If killing a mob is easy to kill on a rank 10 class, jump on a rank 1 class-- then it will be funner! Heck with making progress WHILE you have a challenge. Make the progress in easy mode, then jump on hard mode and make no progress, but at least have fun.

I prefer a hard challenge = higher SP.

Then your being challenged, and getting rewarded for it