At first, organising lunch etcetera is problematic: there's a roll for us (10)
I believe the answer is:
electorate
'there's a roll for us' is the definition.
(as in the electoral roll)
'at first organising lunch etcetera is problematic' is the wordplay.
'at first' indicates taking the first letters.
'is problematic' indicates an anagram.
The initial letters of 'organising lunch' is 'ol'.
'ol'+'etcetera'='oletcetera'
'oletcetera' is an anagram of 'ELECTORATE'.
(Other definitions for electorate that I've seen before include "Constituency" , "Voters in general" , "Everyone choosing" , "Voters as a whole" , "Those entitled to vote" .)