You could examine Italian involvement in the Spanish Civil War, as they supplied an aerial contingent (the Aviazione Legionaria) as well as a substantial "volunteer" ground force (the Corpo Truppe Volontarie) as well as lent naval support.

There is the subject of the Lateran Concordat. To that end there is the new book The Pope and Mussolini: The Secret History of Pius XI and the Rise of Fascism in Europe. The whole "secret" thing is overblown, as it is an old narrative--using fascism as a buffer or tool to combat communism then a growing realization that fascism was inherently violent and at minimum a competitor to Catholicism. That it is presented as a "secret history" is a great way to sell books and get on the talk show circuit, and such publicity would mean that you could join the discussion about the book. The whole process from Italian unification to the signing of the treaty is an interesting one.

The Italian military had a number of defeats and victories during WWII. An examination of the mini-submarine/manned torpedo units could be interesting if a bit dated. Perhaps it could be enlivened with a comparison to modern day special forces units.

Papal involvement in WWI and WWII could also be a rich topic--if overworked at this time. My earlier post on Pius XII during WWII could be of help. The earlier work of Pope Benedict XV to head relief efforts during WWI as well as try to bring the parties to the table for peace talks could also be intriguing.

That's a few off the top of my head, sorry I can't help you with the mafia subject.

Suggestion: The unification of Italy would be a great idea, and then you can see how it impacted Europe as a prelude to WWI.