Obviously there are many differences, but OP is right there are more similarities, they are clearly designed from the same sub-role template. Both are dex-based ranged physical dps, cast time toggle at lv52, TP/MP regen party support, archer/lancer class buffs, an attack that can only be used when enemy is low HP, etc.

I think the way the game is designed will keep forcing jobs to mimic each other. Because each job is assigned a certain party role, their unique skills will always be secondary to the forced requirements of their role. They all need to achieve similar results as other jobs in their category, albeit through slightly different methods.