Overall I love this map of Italy, but I do hope that certain important locations are added, which I've shown in the (crude) map below:
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The first change I think should be made is making Elba its own location, it makes no sense for it not to exist and it's even in CK3. Also, the empire of Elba was a thing for 9 months, so it should be its own location.
The next is making Venice an Island, I know it it will be hard to click, but that's a sacrifice I'm willing to make. The rest of the current Venice location can be renamed to Marghera.
I'd also like to see Monaco be added, in 1337 the Grimaldis ruled roughly the same lands as they do today. But from 1340-50 they would gain the towns of Roquebrune and Menfort. So the perfect location map would see Monaco and Roquebrune-Menfort as separate locations, with an event for Monaco to gain Roquebrune-Menfort. But the more realistic solution would be to have it as one location on game start, as shown in my map. Also at game start Monaco should be a vassal of Genoa.
My final change is to make the Eolie islands their own location at game start, as they were owned by Naples and not Sicilly. However a Frenxh fleet would occupy the island in 1337, so an event should be added for that. Sadly, I couldn't find anymore information about the Frenxh invasion.