Great to hear that you enjoy n8n!
Yes, if you save failed executions (which is the default setting) they will be displayed in “Executions”. Next to the status “Error” there will then be a “Retry execution” button which does exactly that.
That, however, works only for the case you currently explained.It will reuse all the data with exactly the same workflow and retries from the failed node.
What is currently sadly not possible yet is to change a workflow (because there was some kind of bug) and then re-execute it from the start with the same input data. That is however planned to add in the future.