Should diversity be a goal for modern soceity or is it a nuisance to deal with?

I was watching this video to encourage young Americans particularly asian-americans to vote and I was left wondering whether diversity adds value to a democracy or is it a burden? Contrast US with India. The former is a place where diversity has increased over the past century while the latter has been inherently a place of staggering diversity in religion, language, values- you name it. Many conservative Indians believe India should ideally be a Hindu-nation state and uniformity should be encouraged. While that idea never quite took off and hopefully never does, the differences in people does make India a spectacularly hard place to keep together. But western countries like Canada and US have ever increasing diversity. So does it add value and richness to these places or is it a challenge which these countries are forcing upon themselves? My objective here is not to contrast conservative and liberal views but think in terms of perhaps governance and social goals - what is a better society and I am happy to keep 'better' as the adjective here so as to keep the interpretation of my question as open as possible.