An accuracy buff would make sense because it would fit the commando or secret agent class skill set.
Speed is a premium for commandos and secret agents. For the passive speed buff I am only suggesting a slight buff to make it noticable. It would make the game more fun for heavy builds, medium builds, and the speedy light builds would dig it too. It would be useful despite medics having the temp boost for it as it would be a passive buff that stays active for the duration of a player's life in a match like the engineer weap damage buff and kevlar or the medics metabolism buff. It would come in very handy for the carry an item to X objectives and also counter the gripe that the Brink Running speed is too slow. I personally think the running speed is fine for body types but a buff to make teammates enjoy having operatives around a little more is never a bad thing.
Another plus is I've seen (and have personally done it myself) Operatives disguising themselves more than they need to just to try to get the xp. There aren't a lot of Operative objectives compared to the Soldier or Engineer and it would curtail the unneeded disguising having some sort of class buff to distribute to teammates.
Every other class is frequently low on supply due to buffing, healing, building/placing items, and lobbing or shooting grenades. The Operative class generally wastes it's supply pips tossing the occasional grenade when the CD timer allows them too. I think the Devs should give the Operative class something to use those supply pips.
I am curious to hear if anyone likes the idea. I think it would give operatives another fun and helpful way to earn experience and help their team doing it.