I highlighted the one part of your post that was plain wrong. Explanation as to why you should NEVER use primary fire until it gets fixed will be included in my quote link below this paragraph. New Symmetra should only ever be using her sentries or orbs for damage due to the disgraceful failure by the Overwatch developer staff.
Sym 2.0 vs 3.0 Beam Damage - This is a Nerf! - #3 by Pachimari-2662