Please improve the transparency in the history, and differ between deleted (for sysops visibile) and suppressed (for sysops invisible) revisions. Sysops and oversights should see in which way the revision/user-name/summary was striked out. "[deleted]" resp. "[suppressed/hidden/whatever]" at the ends of the lines in the history/diffs/logs/contributions/etc. could clarify that.
It strikes me that I've read "[deleted]" once but I cannot remember where. While I tested it on test.wikipedia.org (have a look at the given URL) I couldn't see any differences between the first (deleted) and second (suppressed) revision.