Of course it's a feature.
It's a cosmetic feature that does not limit gameplay in any fashion whatsoever if you don't have it.
As for the time requirements:
There was infinitely more time requirement prior to arx.
Because you didn't get any at all.
Not if the base game does not have any skins at all (don't mind the default). It's like one thing is missing from the game. If I buy an rpg game, the base game contains some extra free skins for the character in-game. Some "extra" maybe for money, but you have skins included in the base game. That's not the case in Elite.