The C-ERMlas's are great for doing damage outside of preferred brawling range. They keep you in the fight even if your other weapons are out of range. I like SSRM6's more than SRM6's because I have more range and they keep lights in cheek. The C-MG's are obvioulsy there for crit-seeking. TAG and CAP are for the SSRMs and for team support. The single JJ is mostly to help climb hills.
best fix I guess...I don't like the very long SSRM6 cooldown heavy mech. But overall the build makes sense, fire the streaks, and hope one component gets focused(if not, retreat), touch it up with lasers, you be in the ideal range, and finish it up with MGs. Using SRMs one can get a much deadlier mech with the same concept, but less range and the need to aim the srms And this will be my main build for 3x MG timber I guess.