Hive said:
Pelagonio/Ochrid, however, I'm in doubt of... I tried searching Wikpedia for the former, but with no result - even with the alternative spelling. So atm, I'm leaning towards Ochrid (or Ohrid, dunno what's best) unless someone convince me otherwise...
That the area was called "Pelagonia" in Macedonian antiquity is reasonably certain. That modern Macedonians like connecting themselves to Macedonian antiquity is also reasonably certain.
It seems the question is whether it offends the sensibilities of EU2 players (majority non-Macedonian I expect) to have an area that is predominantly Slavic possess a Hellenic-sounding name. That seems to be driving force of the objection.
So it's really a judgment call.
I come down in favor of Pelagonia, simply because :
(a) Macedonians call it that & seem to like it a lot. They should know.

The fact that it is Hellenic-sounding shouldn't count against it if the people of the region like Hellenic-sounding names (e.g. they named their country "Macedonia" after all.

)
(b) Since we give Greece a province with a name connected to Macedonian antiquity, so it's only "politically fair" to give Macedonia one too. This, I think, is of paramount importance if you want to avoid provoking nationalist sensibilities. You definitely do
not need a coterie of FYROMers demanding the name "Macedonia, and that you change the Greek province to "East Macedonia" (and, of course, the converse group of Greeks demanding you change it back). Pelagonia is a good compromise. It is sufficiently evocative of Macedonian antiquity to satisfy the FYROMers & the Greeks can't deny it was there.

(c) that's also what the area was known as in Latin Europe (e.g. the chronicles of the Crusaders passing through the area called it that).
(d) It's the name of a region, not a city or a mountain or a river.
(e) The region shows up in maps under that name, e.g. here's
one from antiquity, here's
a a medieval one, here's
another medieval one (yes I know its in cyrillic, but trust me, it does read "Pelagonia"

]
So that's the extent of the Pelagonian case.