A lot of good questions there Snoopy. A couple of things to bear in mind:
1) Data sovereignty, most if not all govt data isn't allowed to reside offshore. Good for Spark you'd have thought, yet they've made very little headway in convincing the govt to let them host it. Yet Azure, AWS and CDC will almost certainly pick up a lot of work in this space. FWIW when Waikato DHB was hacked in that ransom-ware attack, it was using the Spark data center in Takanini. Though I'm not saying that was necessarily Sparks fault it will have tarnished their reputation somewhat.
2) Scale really matters in this business. AWS and Azure and even CDC have a buying power that Spark will always struggle to match when it comes to hardware and on the Azure\AWS front they put a lot of software development effort into their offerings, which Spark will never be able to match.

So I think Spark will be stuck mostly doing private cloud hosting of legacy systems that can't easily be migrated to public cloud and a bit of consulting. The big end of town will mostly go to Azure\AWS to get the global interconnectivity it needs and the govt will mostly go to CDC and probably public cloud for the less sensitive stuff now that there's NZ located data centers.