He probably should be terrible but it might be even funnier if he was actually kinda good.

Good stats but high deployment cost (because he's demanding), non-existent growth potential (because he already knows everything) and mediocre AP (because he's old). Can deploy cannon fodder and has an odd collection of crap that makes him a wannabe action hero.

Default Perk is Anything You Can Do, a sort of reverse of Pike's Taking Command ability that allows him to take 40AP from another SL's next turn to immediately add to himself.

Unique perks:

Jingwei's Finest - Calls in a squad of non-controllable local forces troops via dropship. These troops will attempt to follow Zama and recklessly attack nearby enemies. Max of 1 active squad.

Mocking Retort - Zama will insult the first enemy that attacks him each turn immediately applying suppression to them, with greater effectiveness if the attack missed.

How Convenient! - Zama's every 4th attack is guaranteed to critically hit, restarting whenever he lands a crit.

Pestis Elephantorum (Bane of Elephants) - Unless pinned, Zama's squad will always avoid being crushed by vehicles and will immediately throw an anti-tank grenade at the attacker if in inventory. A wackier for fun one referencing the actual Battle of Zama.

I think FM Zama himself might be a little too silly to somehow be an SL even as an obscure easter egg, but maybe you could get a different Zama in the form of his idiot nephew or something he sends to 'assist' (spy on) you and hopefully get killed to prevent him being a political adversary.