Havik and Reiko and Kenshi are my favourites.

With the Neather Ream seemingly going to be a force in MKX I think Reiko should be there in Shinnoks leading Shinnoks army.

Noob Saibots ending was pretty well received too, so theres hope for Havik too!

Kenshi is probably the most popular Post MK3 character so I think hes a shoe in.

I think Tanya, Quan Chi and Shinnok all have good chances due to story relevancy.