Not bad, but ll sounds like y in Spanish so the pr. would be more like es-TRAY-a and not es-TRELL-a (not good at explaining but you can also listen to it online) and I feel that would be hard to explain. The meaning is nice but the sound isn't great. I think I prefer
Estella or
Estela. No nickname.
All combos are okay but not great, many contain way too many Ls.