Without knowing what the 70-90 settings are, I can't give a recommendation on using OMA-URI to set them. But Settings Catalog is in GA (no Preview), and we are constantly adding settings to it. But again, without know what settings you're looking for, I can't really give more advice. Note that some of those settings may never be translated to Intune - settings that include the word "Domain" or "Kerberos" as these are on-prem domain terms, and cloud-only devices are managed differently. Or some may be in a different spot in Intune - Firewall settings are not in Settings Catalog, but are in the Security node; Password policies are in Azure, since that's where user accounts live. So, it's possible that at least some of these settings are there but in a different spot than you'd expect, or aren't necessary on a cloud-first device.

I've heard from Customer Success Team that we can provide list of settings from GPO that are not yet supported via MDM and it should be covered in some unknown future. On the other hand, when I've raised support ticket I end-up with recommendation to deploy PowerShell script that will implement that part of CIS which had issue. The last thing is reporting of CIS implementation on the endpoint. In GPO recommendation document there are reg keys for polices from GPO, and Intune MDM caches settings in PolicyManager key so if there is an automated/ semi-automated audit that will check for reg keys based on GPO doc you will probably fail