PoE Arc, Hierophant builds

Hi there! So I'm working on some new builds, and I have two questions about how PoB handles certain calculations. 1.) The first question is very simple and has to do with Flame Blast. When you see the 'cast rate' while having flame blast selected I assume what that is trying to represent is stagers per second, right? In other words, if we assume an unmodded 10 stage max flame blast, and my cast rate on the PoB is say 4.5. That's telling me that I'm casting 4.5 stages a second, so my time to do the 'average hit' damage on top will roughly be 2.22 seconds? So I'd have to divide that

So i think i have finished my pob of the shock slinger. Gotta replace the 6 link arc with lightning conduit and add overcharge support to the 3 link arc but thats about it. i tried to be reasonable with the items since its a league starter but who knows what the actual prices of these will be. Guessing ashes of the stars might be a bit much like this league but we probably have other amulet options anyway. One other thing to note. According to a poe wiki or something i read that spellslinger always triggers helmet first so there shouldnt be a problem with lightning conduit trying to cast

I need someone to walk me off the ledge. Replace 6 link arc with lightning conduit and add overcharge support to the 3 link arc.

POB: I made this build mainly trying to make a cool pain attunement low life build which it used both attacks and spells with the help of battlmage cry and to apply the increase to spell damage from indigon to attacks aswell. In the end i had to gave it up for many reasons like: having to interrupt cyclone to cast BMC, warcry speed isnt fast enough, cant get enough power and you put at risk if surrounded by enemies who can stun you to death, and so on... But now, i used the space of the BMC to use reckoning to apply conductivity

Since the damage on manabond is based on current mana, not mana spent, I've theorycrafted a hiero build based on reducing mana cost of skills as much as possible, which should allow us to control the AOE/damage by controlling our mana. With 9k mana and Pledge, Manabond will cost 4000 mana without any reduced costs. Using inspiration, reduced mana nodes on the tree, jewels, and flask, we can reach 100% reduce mana cost (might be optimal to have at 80-95% reduced though). Mana can be easily restored to full for AOE/MoM purposes using a mana flask (as it doesn't nec