I am very fond of things akin to vim's 'showmatch' mode where when I close a paren or block or etc. the editor highlights the opening element for a second or so and then returns to baseline.
(I have almost no -ambient- highlighting in my baseline but I know lots of people who do and still derive great value from showmatch for the feedback - from discussions with other people rainbow parens style lisp modes seem to provide a maximum overkill approach to that question but I very much prefer maximum underkill in my own tooling even while wanting to be very sure I'm not making it unduly difficult for collaborators with opposite preferences)
(I have almost no -ambient- highlighting in my baseline but I know lots of people who do and still derive great value from showmatch for the feedback - from discussions with other people rainbow parens style lisp modes seem to provide a maximum overkill approach to that question but I very much prefer maximum underkill in my own tooling even while wanting to be very sure I'm not making it unduly difficult for collaborators with opposite preferences)