'別に私達じゃなくても他の誰が来ても喜ばしいことでしょう？' is snagging me here, is it like
'If it wasn't us, wouldn't someone else be equally delighted to come?'
or, because of も, it's more like
'Wouldn't it be delightful if it weren't just us but others came along also?'

Cpt_Skippy said:

'別に私達じゃなくても他の誰が来ても喜ばしいことでしょう？' is snagging me here, is it like
'If it wasn't us, wouldn't someone else be equally delighted to come?'
or, because of も, it's more like
'Wouldn't it be delightful if it weren't just us but others came along also?'

Wouldn't that be '他の誰もが来て'?

'他の誰が来ても' is more like 'Even if it's the others who come', i.e. no matter who got implemented next.