Possible Clues:

• Woolgatherer
• Fanciful thinker
• Armed and ready to move, one has unrealistic expectations
• Visionary, but not at night?
• Walter Mitty, for instance, armed ready for action
• Lot of dukes in Arden and Caliban's isle
• One in a reverie
• Fantasizer, when the sun's up?
• One does lightly what one usually does by night
• One's fantastic behaviour does not need 19 across