I like
Tamar well enough, but where I find it sturdy and ordinary, I love
Tamara which I find luminous. Yeah, I know a lot of people view
Tamara as dated and maybe it is with the nn
Tammy which I don't care for at all. I'd call her
Tamara.
BTW, I pronounce
Tamar as tah-MAR. I don't know if that's correct or not. I've never known anyone by the name. I've only heard of it in connection to the Bible.
Of your combos, I also like
Tamar Celeste the best.