Possible Clues:

• Insect
• Insect; flighty person
• Word that must be added to 1-, 8-, 65- and 66-Across for their clues to make sense [with a visual hint in the grid]
• Toughest stroke
• Stroke goat, perhaps, then run
• Insect, say, with frail wings, by houses
• Idea that a small change can have major consequences elsewhere
• Batsman's opening, wholly in control of fine stroke
• Stroke goat, maybe, then run away
• Spitz stroke