I have all my release activities in a spreadsheet, having to create a release template (one by one) or an entire release cycle one by one, it creates too much work
We currently provide a wide set of functionality with Releases, in particular, allowing you to create custom templates so that its easy to populate Releases with each launch.
At this stage based on current priorities and community feedback, we are unlikely to make additional updates in this area specific to excel imports on release phase plans. We hope you can understand.