.....dont know how people even make builds.
I'm not an expert, but I'll share my general approach to creating builds. Hopefully that helps. I treat content as obstacles that my build needs to overcome. The more of the obstacles the build can overcome, the better the build.
Obstacle 1: Farm t15 maps with 3 mods without dying (no matter the combination of mods)
Obstacles 2
Kill all pinnacle bosses at their lowest difficulty.
Complete the atlas tree
Obstacle 3
Farm t15 6 mods without dying (no matter the combination of mods)
Kill all pinnacle bosses at their highest difficulty.
The process is basically trying to determine what about my current build does not let me overcome the obstacle. Finding a solution and adjusting the build around that solution. Creating a build is a lot of experimenting and trying out things.
My idea was stacking gem levels of shattering concoction and crit chance+crit bonus but my damage is absolutely horrid (Cant kill t10 bosses losing all mana flask charges)
You've identified two problems: How do you generate enough flask charges to constantly use shattering concoction(SC)? How can you scale SC to deal enough damage? I'll focus on the first one.
Charges generation
Looking at your passive tree, you haven't put any points into charge generation.
Combat Alchemy, Cautious Concoctions, Warding Potions and Savouring all seem worthwhile to try.
Next I would look at gear:
Emeralds have "(5-10)% increased Flask Charges gained" and "(10-20)% increased Mana Flask Charges gained" I would make sure every jewel slot has both of those affixes.
With unquies you have Keelhaul, Glowswarm, Shavronne's Satchel, and Birthright Buckle. Some combination of those might help.
To be candid: I don't think there is enough charge generation in the game to use Shattering Concoction as a main skill. I also don't think it deals enough base damage or has enough base utility to justify it's secondary use. However I haven't tested it. Maybe after you try it, you'll see things differently.
