When creating your Leader for the very first time, you'll notice that there are several unique clothing options. The shape an style of the clothing is identical to the body clothing of the five classes, but the Leaders have colour variants. What I propose is that all survivors can be further edited to have different-coloured body clothing, from a handful of class-based variants. Specialised survivors are restricted to the style of their class, but Leaders can make full use of all options, as seen at the beginning of the game. For example, a Scavenger with the jacket-and-bandana look can only use the re-coloured versions of that outfit and could not suddenly use the makeshift armour style unique to fighters. However, a Leader could choose from either style.
This would be great for immersion and customisation, and is such a small and easy-to-implement feature that would enhance the variation between survivors. To see what I mean by different variants, refer to the image below.
One Leader has a unique outfit only available to leaders. The below Leader has a variant of the Scavenger style; a red and brown version of the lighter, purple Scavenger outfit. The last one has a burgundy and black version of the beige and blue style of the Engineer.
Make sure to +1 if you would like such a small change and thanks for reading, not to mention your support!