Thinking on the images of first level adventurers being dressed in near-identical (to the point of uniform) armour, it robs it of flavour. Consider: picking up a Sword in the character creation might suggest itself to a long, thin epee or a cutlass or a scimitar (presuming the system being used doesn't give different stats for each). Similarly, choosing a Polearm might suggest a Billhook or Halberd or Glaive.
Just saying that you wear chainmail or leather (studded or otherwise) or laminar - it doesn't offer quite the same options. Now, this does offer the opportunity to gain interesting armour at later levels - a breastplate of Dwarven manufacture, an Elven cloak, a helmet made from the skin of the Nemean Lion. But it feels less characterful, after a fashion.
So: this is meant to be a selection of armour, plausible to be found by a aspiring adventurer and a touch more interesting than a shirt of mail.
Gladiator Armour Armour that protects only certain parts of the body, forcing the wearer to favour a particular fighting style - for the amusement of the spectators. Perhaps not the first choice for the aspiring dungeon explorer, but a viable alternative. It might be possible to incorporate new pieces of armour into the ensemble - but at a cost both financial and aesthetic.
(Exactly this kind of thing, in other words)
Branded Armour The armour you have obtained is or was emblazoned with the symbol of a particular organisation. It might be a military or religious order, a merchant house - or something else entirely. This might have no effects in battle - but have a very definite effect in social scenarios.
If, then, you find or purchase a breastplate bearing the sigil of the Gilded Regiment of the Imperial Legion, you may find that anti-Imperial partisans object to this - or that the Imperial Authorities object to your use of something from their armouries. Even if you have the sigil removed (which may be costly or unsightly) there are those who will take you for a deserter trying to conceal his crime.
Cavalry Armour Armour designed to be those riding into battle. Perhaps not a problem at all times, but liable to prove a problem at a critical moment. Moreover, consider that in the fantastical settings one might inhabit, the beasts of burden may differ significantly from the horse or camel.
Marine Armour Armour worn by seaborne soldiers. Capable of being removed swiftly at need when one falls overboard and treated against rust - if somewhat less robust than other types.
Concealed Armour It doesn't look like armour. But underneath the doublet, there are layers of plates - detectable to those who know how to look for them, or those close enough to touch. Of course, once battle is joined, the concealment is ruined and must be repaired by a skilled tailor. Moreover, the armour, in order that it can be concealed, is principally made of unlinked plates that are not always reliable at stoppingthe heaviest blows.
(One other good example of flavourful armour for starting characters can be found over at Dungeon of Signs. I love these sets of starting equipment - but they are explicitly part of the setting. This article is hopefully more general purpose).