This pleases me. Imperial Fists are the perfect choice of 'default' Marine Legion. They take standard bolters and chainswords and make them awesome. Yellow looks so good when weathered properly.
And Heresy-era Iron Warriors > 40K-era Iron Warriors.
They're just so much bleaker than any other Legion; taken for granted by every other Legion, treated with contempt by their Primarch... They don't even fall to Chaos so much as turn from the Emperor into absolute nihilistic despair. The only reason they feel hate is because it's the only thing that can cover over the fact there's nothing left inside them at all.