We have an absolute ton of playbooks from different people on these topics as well as some great courses on this especially this one from Tim Wilson
here are some playbook examples, feel free to use the search to explore some more. And if you have any questions please leave a comment and we can get you the answers you need.
Regarding your process
What we have found the most challenging aspect at times is to make 100% clear how the metrics and dimensions, segments etc are defined to everybody. Especially when you start mixing tools and platforms and the same metric can be defined in X number of ways. For example
I believe getting some specificity in the data request upfront helps, but also making sure that these definitions are communicated effectively and that there is alignment on them is key.