Alyssa and
Elissa would be almost the same. Uh-LISSA vs. ill-ISSA. But I think the difference would be so slight as to be unnoticeable.
Amber and Ember are noticeably different. AM-ber, EMM-ber.
Amelia sounds like uh-MEEL-ya.
Emilia begins like "ih": im-MEEL-ya. Again very very slight and probably almost unnoticable.
Al and
Elle are noticeably different.
Al is more nasally; ryhmes with
Hal.
Elle is said just like the alphabet letter.
Alice is nasally again, AL-iss.
Ellis is not. L-iss. (actually, we have a street named Ellice here and I think it is sooo beautiful, the name I mean). The difference is noticeable.
I live in Mid-Canada (Manitoba).