If the Italian authorities resolve the issue of CIA then I believe this along with a daily BGY service could work extremely well fom BOH with it's leisure orientated pax. Look what happened when the Italian Gvt tried to push operators out of LIN to MXP. They revolted and all still operate from LIN.
I would have thought Italian destinations would be way ahead of any German service in the likelyhood stakes, though I would like to see a German destination back. If not Hahn, then somewhere like Baden Baden which gives easy access to southern Germany.
YYZ or any other canadian city have never been operated to from BOH. There was talk of a Canada (joint) service (with BFS ?) a couple of years back, but it never materialised.