The Flash Season 3: 7 Theories On Savitar's True Identity
5. Eddie Thawne
If it isn't Ronnie, though, maybe it is another Team Flash boyfriend who died at the end of season one in order to save Central City? As that is a very small club, you've probably guessed that I'm talking about Eddie Thawne.
Eddie has long been theorised to return to the show as a villain at some point. Largely because the character somewhat resembles Malcolm Thawne, a character from the comics who is the supervillain Cobalt Blue. For example, when Eddie dies, you can see that he is wearing some kind of medallion around his neck. In the comics, Cobalt Blue derives his powers from a magical talisman.
It would be very easy for The Flash to change up the character and make Eddie's supervillain identity Savitar and his magical talisman the Philosopher's Stone. Presuming that Eddie had turned evil for whatever reason, he would have a strong case to hate Barry Allen. Barry has pretty much stolen his life: in particular, his fiancee Iris.
There are a lot more points pointing in Eddie's favour, then, but having him be Savitar would still probably suffer from the same diluted effect as Ronnie.