I know three Elenas. Two are Russian and pronounce it uh-LAY-nah (well, I'm sure they pronounce it differently in Russian, but that's how they say it in English). The third is Cuban and pronounces it EL-eh-nah. I've never met a
Helena in real life, but I know one on the internet and she says HEL-eh-nah.
I'd say eh-LEH-nah for
Elena and HEL-eh-nah for
Helena.
Alaina and Elaina are both uh-LAY-nah. I've met one
Alaina who said it that way.
I'm from California.