Balor is too much of a weakling for a boss, everyone can easily dispatch him, no matter the build:
He doesnt have high levels of mech/heat resistances, unlike Industrial Bots, that can tank a lot of damage easily.
Can be stunned, easily dispatched in 1 or 2 turns
Can be incapacitated, mental breakdown makes sense but Balor be trivialized by flashbang
He has awful detection, despite the fact he has a mechanical eye
Has no real tanking abilities, it just happens he has a lot of HP on top of a mediocre metal gear set
Can be entangled, come on the guy must have like 20 STR why he can be entangled
He's way too easy to dispatch, compared to Braenkaster, he's a real tought bastard to bring down, and he's a proper hammer boss
My suggestions are:
>Give Balor tanking feats, such Stoicism, Conditioning, Fully spec'd Last Stand, also high Resolve and Fortitude
>Inmune to Stuns (like Magnar) and Flashbang Incapacitations
>Give him Sprint and Adrenaline
>Give him stupidly high detection or straight out True Sight, if you consider his mechanical eye a camera of sorts
>Give him a stronger metal armor or a metal armor unique that actually makes him tanky
>Make him inmune to entanglement/inmobilization
This way, Balor will become an actual threat and not a human punching bg