A good list. The article states - assuming you're a developer and not a dba, so the tuning issues are more on a dba's plate.
What keeps many of us up at night is not having our heads around the db well enough to understand what's going on. Performance tuning while important is not mission-critical unless there are serious user complaints.
The concept of (potentially) obsolete elements is another issue. The need to delete them is rarely mission critical, deleting something that's still needed becomes that. Yes, there can be issues with available space (large tables no longer needed) and it's a pain to wade through a bunch of no longer needed SP's, etc. My recommendation is document as many of the objects as you can where used, etc. - may take weeks or months. Anything not obviously used can get the XXX prefix treatment (or copied to an archive location) for at least a year.