Hello JeremyTBradshaw, Sorry I did not see this earlier. This ended up in my junk folder.
Your number 2 there is the answer "Skip ConfigMgr altogether and just implement Intune."
Those customers that do not have ConfigMgr, I would strongly suggest they go straight to Cloud Only, period. The strategy around Cloud-First is simple and will also cause the innovation of processes and workflows. If you have no management solution today go cloud-only, DO NOT "knee jerk" to an on-prem solution because "I can't do ____________ with Cloud Only"! When I hear customers say "I can't", that means they just have not found another way, so modernizing and innovating some processes is what I try to explore and unpack.
Eventually, you should end up validating your business needs can be meet with Cloud Only management or you validate that you need small and simple on-prem to fill the gaps. This is an exercise I recommend quite often with customers I engage with that want to go Cloud Only. I will also add if a customer does land on Cloud Attached ConfigMgr it is small, simple, & efficient (think set it, and forget it).
Microsoft is ALL IN on Endpoint Manager (that means ConfigMgr & Intune), so I also want to call out we have stated this many times over publicly. We have no plans to minimize the investment in Configuration Manager and for Customers that have Configuration Manager, we strongly suggest they cloud attach. Cloud Attaching ConfigMgr is by far the easiest and simplest TRANSFORMATION to Cloud. I'll end with keep in mind these things don't happen overnight and some customers need time to modernize not just their technology and processes but also the mindset.