It looks good, it's a good idea to have golden areas in his armor by Celestia's guards, I do not think Tempest likes wearing a helmet because he would look like a terrestrial pony for his broken horn.

I like the idea that you design the Twilight guards but Twilight being the Princess of Friendship would not want guards to be closer to everyponies and other creatures, so Tempest would be like a presidential bodyguard