Notes: Kutch is not an island.
It was before the 1800s, wasn't it?
No, there were a few earthquakes there, but from what I read, it has only recently become a penninsula of kinds, never an island, show me why you think it is an island, though, I might be wrong.
https://upload.wikimedia.org/wikipedia/commons/6/65/Gujarat_Gulfs.jpg (Kutch is south of its Rann and north of its Gulf)
Is this just a more traditional name or something? The one called "Inner Gujarat" might also need some attention, I don't think it's very well named at the moment.
Gujarat usually refers to a bigger site - wherever the Gujarati culture is spread. However, Saraushta refers to the penninsula vicinity, and Kathiawar refers to the penninsula itself. I think Saraushta is the better name, though, as it has been attested very early on to refer to the site, while Kathiawar gets its name from the Kathi folk, who migrated there sometime in the 1200s to 1400s, and probably was coined later.
Also, yeah, I'll probably find a better name for "Inner Gujarat", but later.