You can sort the tables of reverse dependencies by clicking on the column headers.
I wouldn't have thought about clicking in the columns headers. Maybe you could show the order arrow already in the beggining, before any clicks, this would give a hint.
- Rev. deps overview for all packages; is it useful?
Sure! Do you think it could be complemented with a graph view? I liked this, from graphviz page: http://graphviz.org/Gallery/undirected/softmaint.html
- Is this the best way to present the information?
Just cosmetics: in the individual package rev. dependencies, what do you think of using two columns, one for direct dependencies table and other for indirect dependencies? This would remove the need for navigation links in the main table. Also, here, if it's feasible, I think a graph with just the central package and 1fst and 2nd order dependencies could be usefull. Best, Maurício