Hmm. I want to like it, but it just reminds me of the infamous oil substitute Olestra (
http://en.wikipedia.org/wiki/Olestra). :/ I love
Alessia, though.
Also, Olessia doesn't make sense as a transliteration of Олеся. It would be transliterated as Olesya (я=ya) or maaaaaybe Olesia, but there's definitely only one S.