Honestly, purple has a very big following among the ladies on the SN forum. Though I'm not as big on purple as some of the other gals, I can give a break down on the purples as I own most if not all of them.
Aubergine-Blackened
plum. This one is very very dark and very pretty.
Bewitched-Very awesome brilliant purple. Great liner shade. It's one of those shades you have to have just because it's so darned pretty to look at.
Lavender-deep matte purple shade on the greyish side so a bit of a smoky purple
Plush-Again, one of those shades that just too pretty not to have. It's purple and copper with a nice sheen and incredible depth
Thistle-deep matte
plum on the greyish side.
Vacation-fairly true deep purple with a slight shimmer.
Velvet-Gorgeous Gorgeous Gorgeous grapey shimmer. very deep purple
Vineyard- a crowd favorite. This was a GWP color that became very high demand and was added to the line. It's a multifaceted lavender shade with lots of different colors added into it. Probably a bit lighter than you're looking for but definitely worth trying out.
I will also refer you to the smokey
plum quad which is beautiful and designed to make a full purple eye ensemble.

Velvet- deep shimmering plum with hints of copper
Taffeta- satin pearl muted deep plum
Satin- light muted plum
Chiffon- shimmery light lavender
The rest of the purples are probably a bit lighter than you're looking for, but I am very fond of breathe.