Central European means adding support for accented Latin to cover: Croatian (Latin), Czech, Estonian, Hungarian, Latvian, Lithuanian, Polish, Romanian, Serbian (Latin), Slovak, Slovenian and Turkish. For font geeks, we'd be looking at including the http://blogs.adobe.com/typblography/latin_charsets/Adobe_Latin_3.html character set.
Cyrillic support would likely mean a follow-up release. Basic “Adobe Cyrillic 1” would cover Russian, Adyge, Avarish, Balkarian, Belorussian, Bulgarian, Chechen, Darginish, Ingushian, Kabardino-Cherkesian, Kumykish, Lakish, Lesginian, Macedonian, Mordovsko-Ersatian, Mordovsko-Mokshanian, Nanaish, Nenish, Nivkh, Nogaian, Selkup, Serbian, Tabasaranish, and Ukrainian.
Adobe Cyrillic 2, which I would likely do if I did Cyrillic at all, would add support for: Abaza, Adyghian, Avar, Buryat, Chechen, Dargin, Dungan, Ingush, Kabardian, Kalmyk, Kara-Kalpak, Kazakh, Kyrgyz, Lakh, Lezgi, Mongolian, Tabasaran, Tajik, Tatar, Turkmen (Cyrillic), Tuvan, Uzbek.
I might throw in support for even more than that, but first let's worry about the funding!