Crossword Genius

I’m so utterly fantastic on many levels! (11)

Ross

I believe the answer is:

multistorey

'on many levels' is the definition.
(on multiple storeys or levels)

'i'm so utterly fantastic' is the wordplay.
'fantastic' is an anagram indicator.
'im'+'so'+'utterly'='imsoutterly'
'imsoutterly' anagrammed gives 'MULTISTOREY'.

(Other definitions for multistorey that I've seen before include "Type of car park" , "Built on several levels" .)

I've seen this clue in The Times.
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