Hello.
As far as I know, "less" doesn't go with a one-syllable word.
less big than......... (incorrect)
less tall than......... (incorrect)
less far than.......... (incorrect)
less old than........... (incorrect)
less fast than............ (incorrect)
less deep than........... (incorrect)
If I am wrong, I'd love to stand corrected.
And if there are exceptions, please let me know.
How about 'less fun than.............'?