[Snake]

All seem pretty solid. I think Rogue could get Dark Bard instead, leaving Alchemist to Mage.

Though in regards to Dark Bard itself, I think Dev was also once upon a time in agreement to make Music-oriented combat be its own category and class with its own promos. I think it was 'Bard' -> 'Dark Bard'/'Maestro'/'Dancer', one of the biggest requests in the past.

So, with the slot open, I'd suggest the Rogue's fourth promotion be "Scoundrel". Which uses illegal gadgets to deceive and confuse their enemies, pulling 'trickery' to the next level, such as going invisible for non-player enemies, rendering them completely untargetable, and appearing from such clock-and-dagger approach to backstab them into a Vorpal Strike, being able to use Steal from a distance, able to refill their Pocket Sand when they're knocked down, able to do a 'Low Blow' on enemies to stun them, and after their tools and tricks are wasted (for being a 'once per fight' deal, as logically the enemy would be expecting them), they disengage and utilize handguns, effectively for the rest of combat.

Their gunplay would involve sliding around, shooting and attempting to go for blind spots for advantage.