Now, I don't know my Kanji (at all), but I find it interesting how different the English name is...Haven't all of the other regions at least sounded phonetically similar to the original Japanese? I saw your discussion about Sinnoh.
Yeah, Isshu's the first (Main Game) region to actually get full on renamed.
Kanto/Johto are literal romanizations since you can ignore the u/h.
Hoenn is on the same area as Sinnoh. It's the same name as the Japanese; but, the spelling has been altered to make it look less awkward. Houen and Sinoh would look a bit awkward when you look at how they handled Johto and Kanto.
But, it's all up to interpretation.
Unova isn't a bad name, and appears to have multiple meanings. But, I just saw it as Uno (one) and Va(riety). Which is what Isshu is apparently supposed to mean.
But, it's just weird now of all times to start full-on renaming Regions (for the main series). That's the only problem I have with this. And on top of that, now we have to deal with 6 different names for one region: Isshu (Japanese), Unova (English), Unys (French), Einall (German), Teselia (Spanish), Unima (Italian).