reddit comments expand/collapse child comments only at selected depth/level

To read reddit conversation threads more efficiently, I want to expand/collapse comments and their children at will. Specifically, I want to create a link next to [+] or [-] like [+++] or [–––], depending on the circumstances, that upon clicking will expand the child comments (n+1) of a given comment (n), at any depth in the thread. See the pictoral demonstration with captions explaining what I'm looking for here: [login to view URL] I want to 1) start with all comments collapsed except top level comments (level 1) (done already!). The child comments (level 2) of the top level comments (level 1) should be collapsed but visible. This will give me a at-a-glance visual indication of the level of commenting activity for any given level 1 comment. 2) be able to expand all child comments (level 2) of a selected top level comment (level1). The level 3 comments should be collapsed for every level 2 comment. Be able to do this at any level: expand all child comments (ie: level 4 or n+1) of a selected comment (ie: level 3 or n), without expanding the child comment's children (level 5 or n+2) 3) Be able to do the reverse: collapse all child comments (level 2) of a selected top level comment (level 1). Be able to do this at any level: collapse all child comments (ie: level 4 or n+1) of a selected comment (ie: level 3 or n) 4) optionally, make it so that upon page refresh, or later visits, that the expanded/collapsed states are remembered and restored in a way that works with Reddit Enhancement Suite (RES).