My team is setting up Agile using kanban methodology in a marketing operations team. We are still dialing in some details as only Workfront tasks appear on a board. We are looking at how to best represent an asset (brochure, email) and not the individual tasks that are required to create that asset. Will keep you in the loop as we start to use it.
I'd also love to hear about your journey with this! I'm the Marketing Operations Manager for my company and we've been talking about going agile for awhile since we're retail but haven't made any moves yet. A success story would certainly help push us in the right direction.
For IHA's we have found that adopting Agile principles for different tiers of projects has been the best way for teams to embrace it. What that looks like from a high-level is new concept creative (tier 1) works very well in an Agile Scrum approach, production level work (tier 3) works very well in a Kanban approach, and repurposing/adoption of existing work (tier 2) tends to do better in a hybrid variation between waterfall and Agile. So maybe the team does daily standups to understand progress but doesn't work in full sprints.
We actually published a whitepaper on this topic that you can download for free here. https://cellainc.com/insights/whitepapers/2020/01/20/making-agile-work-house-agencies/.
Hope this helps gets the creative juices flowing!