PoE Valyrium, Channelling builds

Hi I absolutely love this skill and the Elementalist version of it with the golems and poured my heart and soul to push it and would love to make it so I eventually am able to clear and beat all the game's content including the pinnacle bosses(at least the non-ubers). After asking around a bit in the community it became very apparent to me from hearing a lot of doom-saying from others regarding this type of build for endgame content -- I have never gotten to pinnacle bosses before and so I have no clue what is expected from a character in terms of stats to acomplish going through them; In