Big Bang Bishop build

Angel Ray and Big Bang will be your primary attack skills. Big Bang scales awkwardly and has 80% of its max damage at level 1, so it is a lower priority skill to max. Genesis is actually an "ultimate" skill now, not just your primary mob skill. It does a lot of burst damage, and you use it to clear the screen when you see a lot of mobs. The main reason to add points into it is to lower the cooldown. I'd say add at least 1 point, but put it as a lower priority than AR/BB. Same priority level as Infinity.

Bahamut attacks once every 3 seconds and Mana Reflection is definitely a very low priority skill.

And yeah, the 1st-3rd job skill distribution looks fine.