Pretty impressive so far.
I like the idea of characters from different games but it should be limited to avoid to overladden the cover including all games.
If you stick with a single barbarian, could you try to alter the angle of view a bit: Barbarian looking from left to right (tomb, grave, whatever), so you have him almost from his right, more of his back. Accent on the sword (reflection?). The double-bladed axe is way too dominant for my taste. But that's just my imagination, you'll find a solution for sure.
Did our fallen comrade had a favorite animal? Maybe you could add that animal sitting on the tomb or standing at the side as a kind of totem.
Man, I really regret I hadn't the chance to see him in person. Well, will I ever see anybody in person?

Had a choir in my heart and had to kill it to survive.