Actually I like to keep that the Espers are the only way which can disband the party temporarily. For the uniqueness.
I do like some of the special things you've done. Other problem is that where is such a sword obtained. The item can't have too many 'if'. There's that 488 letter max count.
EDIT: Well actually that is not the reason. I just don't like to play with the dragons. I really don't. I don't want any strange dragon mutations pop up suddenly.