I love customisation in games. Partly why i'm such a huge fan of RSV 2. However, i don't think a system like that would work in BF. If there was going to be customisations, then my ideas would be:
Armor detail colour- Ideally could be used as if to represent a unit, however the real purpose would be for clans and such. I'm talking about a whole colour change, Just small bits, like outlining on shoulder guards etc.
Barrels/Scopes- For different play styles. I.E choose between different zoom lengths for snipers and barrel sizes- Maybe bigger barrel, more damage, less shots or something. Just tweaks like that could add abit of diversity yet still keep the game in tune with its roots.
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