A regal date made much of (1,5,4)
I believe the answer is:
a great deal
'much of' is the definition.
The definition suggests a singular noun which matches the answer.
'a regal date made' is the wordplay.
'made' indicates anagramming the letters.
'regal'+'date'='regaldate'
'regaldate' is an anagram of 'greatdeal'.
'a'+'greatdeal'='A GREAT DEAL'
Can you help me to learn more?
(Other definitions for a great deal that I've seen before include "Some bargain" , "lots" , "many" , "Very much" , "Poker player will be hoping for this" .)