I've played Italy in AoI3.0 (Demigod or Deity equivalent, can't remember), and I don't think they're much fun in a SG (or anywhere else!). Only AoI game of 10 or so I didn't finish, being clearly in the lead.
While it was really interesting to get them started (lending cash everywhere, to rush stuff + beat on France very early for Marseille and their North African holdings), it was outright boring from midgame once I had a suitable empire. It takes ages to get enough RM, and war...your mid+lategame units don't have a dent on their French, German, English or US counterparts, so it was all about insane amounts of artillery.
US or Japan offer a lot more fun and viable winning chances.
Just my 2c.