If EC was a well designed skill then the interesting aspect (flask usage) would be extremely beneficial to the skill. As it is, this is not the case.
This isn't going to be a math heavy post, but long story short, you can only regenerate so many flask charges, and that number is way lower than what you need to constantly use sapphire/topaz flasks outside pure mapping. The new sapphire/topaz flasks are quite good, but really only modestly better than just slapping on a diamond flask and require massive investment to sustain. The recent 3.21 change to EC which makes you use massive amounts of flasks with more projectiles makes this even worse. As it is, hit based EC is basically either 1) extremely attack speed limited or 2) abandons the most interesting aspect of the skill. I'm here to tell you option 2 is immensely better. So much so, the ability is quite strong, but only if you just give up on sapphire/topaz flasks. If you compare EC to it's most similar skill, Ele Hit, then the fact that EC can shotgun is just immensely strong. The change with projectiles consuming flasks is meant to dissuade from this strength so we just ignore it.
Starter pob: https://pobb.in/GjPiI9xEC_O3 Early build. Probably some things that need to be fixed.
totally theoretical finisher pob: https://pobb.in/qS_aVcUOZPdv - everything in config just fixing broken stuff. even if you unclick everything its "good". could be shit though who knows.
Also I'm pretty sure this is hands down the worst league to do EC, but there are a few nice bonuses with things like the new Multishot notable. You don't get a weapon in "weapon are insanely good league" though. I don't recommend anyone else start this, that's not the point of this post.
99% of the time I am a huge GGG shill. I thought Archnem was fine as it was. But this is a longstanding gripe of mine and the horrible offering GGG produced has led me to this build.
TLDR: EC is good. Hit based EC is currently horribly designed. Also hit based EC is super strong but only if you ignore 90% of the point of the skill.
TLDR2: happy to take dissenting opinions, but please, do provide me some reason you disagree.