IMO, it may be Graptopetalum superbum. Leaves should be relatively thick, and wider. It has lots of farina (powdery coating) on the leaves. Echeveria Perle von Nurnberg and gibbiflora are similar looking (probably not gibbiflora, it usually has very symmetrical rosette), with thinner leaves. In good (sufficient) light, leaves get purplish cast. If by 'ghosty' you mean plant with common name ghost plant = Graptopetalum paraguyenese , it would be smaller, with thick leaves too. Here is photo of G.superbum:

Leaves on your plant look narrower and longer than leaves in my photo, but I am looking at the very center of rosette...It looks to me there are many offsets - are they from this plant? I am not sure G. superbum will offset so prolifically. Sometimes it is difficult to be sure if not grown in best conditions (light, mix etc). Flowers will help a lot to ID.

thanks so much!

I dont think those are offsets but other plants grown from leaf prop. it hasn't ever flowered, so I dont have any pictures. thanks for the advice!