Thoughts a my first build. OOS Crit

Hello, i figured this would be a good league to make my first build since its all about crafting. I really enjoy crit builds a lot, (the shatter sounds so nice) so i decided that i would give orb of storms a shot. I have played this once and it felt pretty smooth. I know i don't have items on this POB because those seem straight forward enough to get. The only concern i have is the skill tree. I have tried to design this for HC but somehow this feels really bad. I think i understand the gem links as well but i'm not sure if i'm using the correct ones. Anyways, i just wanted some help making this and get some tips for future builds.