Now, Disney did exactly this, reducing the large canon to only the movies, the television series and one unfinished script. This means that The Force Unleashed became part of the Legends universe, which is part of the larger Expanded Universe, but is more of an alternative take on the canon than anything else.

Will starkiller ever be canon?

Galen Marek, a.k.a. Starkiller, is not canon at this moment. Before Disney's acquisition, The Force Unleashed was part of the “C-Canon”, meaning that it was canon unless it contradicted other material. After Disney's acquisition, the game and its protagonist ceased being part of the canon.

Did George Lucas consider force unleashed canon?

The situation isn't as cut and dry as some may have believed though, for one very simple reason: The story was canon, but the game never was. Over the years, Lucasfilm developed what can be best described as tiered canon.