Possible Clues:

• Slightly better than
• Superior to ... and what can go with the starts of 3-, 7-, 9- and 24-Down
• Superior to
• Clearly superior cave about to collapse
• Much better having unexpected U-boat victory described by expert
• Notably better than the alternatives
• Superior to, and a hint to the first letters in 3-, 28- and 9-Down
• Distinctly superior cave about to be transformed
• Redundancies in senior management? Excellent
• Superior