Yetos, by full colonization you mean that they were the entire population? I'm sure there were non Greeks in the population that became Hellenized in both cases of colonization.
by colonization we mean people who devaste and colonise,
by Hellenization we mean accept the Hellenic culture and speak Greek,
compare like America today,
All colonists, All colonies in the begin they had names like new Amdersdam, New England, Nova Scotia, etc etc
later they moved West and made Americanization,
Today is called US America,
and in new York are many Italians as your flag, but are Americans,
But if America did not revolt to England, like Australia
in both areas, we have partially Anglicanization,
a good example of Hellenization are the Gauls of minor Asia, Galatians,
a good example of colonisation is S Italy,
to your answer consider who were trully Romans at 700 BC, and who 100 AD and who at Sancrum Romanum Imperium, and who at 1453 Con/polis, and 1463 at fall of Trebizond,
anyway the termination Byzantium entered by Hieronymos Wolf and the Fugger by writing Corpus Historiae Byzantinae
until 1562 was the East Roman empire, and her first emperrors were Romans, although many are said about their origins today, cause everybody claims whatever, and I do not know something else than the ones which are written,
for example if someone was Spanish and become Roman centurion and his son born in Balkans become emperror, nobody, only the written
or a Greek or an Iranian, become Roman and then become prince or Duke somewhere in the West,
or a Numidian or Egyptian etc etc