[Snake]

All of those are main class-only skills so they don't stack with each other aside 80 APT memes.

Archer is a critical padding that only works with those weapons mentioned, mutated weapons should not apply, ideally.

Soldier (Bash) requires the enemy to be immobilized, slowed or clumsy to inflict knockdown (which is a status infliction chance), and requires a shield to be equipped, alongside needing to crit the enemy as a main class soldier.

Martial Artist's 'blitz' part comes from Twin Dance for fists, they may attack twice in 'attack damage instances', but not in 'amount of attacks done'. This was made envisioning to make the Martial Artist who is very limited into a certain equipment (due to Weathered Body's condition) set and weapon set, and duration set. The intent of this skill is to make a basic hitting Martial Artist glue to an enemy and as long as they're in melee range, they can overwhelm the enemy, but if the enemy breaks melee combat or disengages, they'll be forced to chase again and get lucky with another crit.

I'd think Bard's one is fine, since again, main class only, but by then onwards I ran out of genuine ideas, because none of the classes presented want to critically hit enemies. So the playstyle should be something new for each one of them.