I've just finished reading the book.
These are my ideas, but I'm not so sure:
Dorian Grey ESFP (dominant Se)
Lord Henry Wotton ENTP
Basil Hallward ISFP? (I really don't know, but I'm pretty sure about the I and the F)
Sybil Vane ENFP
I don't know about the minor carachters.
What do you think?