I see you're in Australia, and Australians have been known to say things that sound strange to AmE speakers' ears (like mine) so I'm hesitant to say it's unnatural or wrong, but most natural to me would be:
1. It must have been a fun working environment, wasn't it? or right? --Americans are reluctant to use "must" as often as
other English speakers, especially in tags
2. You're totally/completely right. --Your sentence sounds like our "hit the nail on the head" but we associate that with
correct assessments, which actually might also work in your situation
3. Is it your turn next? --Or even simply "are you next?"
(not a teacher, just a language lover)