New to the universe of 40K and already Roboute's breaking my heart. I can't help but feel so sorry for the Ultramarines, knowing their "father" was killed by their "uncle" in a duel to save the empire.
I'd dare say worse then what the Blood Angels got. Blood Angels only feel the agony, Ultramarines saw it happen.
We don't often get to see Primarchs in something other than power armour, do we?
You have my respect for this portrayal; it's quite difficult to capture the individual personality of a character as inherently over-the-top as a Primarch. He looks like exactly what he was to his Legionnaires, everyone's beloved father, level-headed and caring.
My only criticism is the colour. Desaturated, more earthly hues combined with the style of uniform he's wearing are something we've come to associate mostly with post-heresy Imperial Guard officers. Of course, the inverse Omega, the leather straps and the gladius are giveaways, but, well, I had to find something to nitpick!