[Warhammer 40k] chaos space marines are like regular marines.... But 100% more intimidating and interesting

Each different faction of chaos space marines have their style and looks outside of normal space marines. But the reason why they stand out is due to each faction having tremendous differences like unique body horror for the death guards zombie like appearances, demon possession for the world bearers turning normal marines into monsters, and even going as far as the iron warriors replacing most of their bodies with machines.

One issue I've always had with normal marines is despite their niches in some areas of war, they all look almost identical outside of some extra pieces of armor or different colors for each faction.

The Chaos space marines bring more to the table with unique armor sets and helmets, body horror and all around demented appearances, and each faction being tailored to each chaos god.