Interesting. I actually find it easier, but it could be because everybody in my team is doing their job, and contributing in other parts as well.
When it comes to 'jobs' and 'people doing their jobs' it's roughly proportional, more people means more decks to make, more cards to salvage/discard, more duels to arrange, etc. so generally it shouldn't matter how many people there are.
But when it comes to management, more people is definitely more work, and with larger teams we'd need more managers, more funds, more customers
and more corruptionOn the other hand, when some people fail to do their jobs and go missing, other people are busy with personal matters, other people live in different time zones so it's hard to meet everyone to discuss some matters etc... other people lose their fingers due to heavy injury (yup, that's serious), now managers job ain't easy... but is definitely interesting