In the Search Center, under the "Matches" tab, a list of all cells containing the search string comes up. I sometimes find myself using this as a handy way of iterating through a repetitive task.

Being able to remove and reorder search results would be useful.

It would also be nice to be able to highlight several of them, and alter them as a chunk. For instance, suppose I have a large data table, with null values represented as 'NULL'. I could search 'NULL', and highlight all the null values, say by changing the background colour or font. This might cause problems with multiple ranges; I'm not sure how feasible it is, and there comes a stage when a script approach might be better.

The Search Center is already very useful, much better than the standard Find/Replace.