I really, really love
Valko! Also
Nikolai,
Aleksei and
Dmitri, which I see are on your list as well; and
Marko and
Viktor as well. And I sorta like
Mikhail, despite the fact that I don't like
Michael.
For girls I love
Tatiana,
Nadya (though I prefer it
Nadia),
Elena,
Milena,
Selena,
Larisa (though I like it better with 2 S's,
Larissa) and
Valentina.