Hey Philipp -
We're in the SaaS/app space and have been using "strict" Scrum for a couple years now. We're also about a month into our EOS journey as well. First off, I'd love any additional insights from folks further along in the journey!
From my perspective, the rocks align nicely with the "new" Scrum concept of The Product Goal. Additionally, I think rocks serve as a "compass" to ensure that your sprint goals and product iterations are aligned with the needs of the overall business.
One related area that I'm curious to understand better is how to align solving issues that arise during the weekly leadership to-do list review. Specifically, how much importance do those issues take over the committed sprint items? Seems like there's the possibility to introduce quite a bit of churn/replanning into your sprints, which are typically longer than the weekly meeting cycle of EOS.
Best of luck with your implementation!