At present, to see my list of hidden collections, I go to the collections page, then click on "your collections", then click on "private collections." But why not have a button "hidden collections" next to "private collections" (which is itself next to "public collections"), given that there seems ample room to do so? It would save having to take the somewhat convoluted path through "your collections", and may have the additional benefit of encouraging the use of "hidden collections" where appropriate rather than private ones.
P.S. The previously discussed "ignore this collection" feature is sorely needed (sorry to nag).