If you don't know how to build a good Brawler with this Mech, simply go for the Whooosh! Because it has 3xM H-Points. Now with the upcoming ECM-Nerf, u don't even need the Tag and so save the E-HP for Backup Guns. Just wait for the Lock and then begin the endless Spam. Weapon Groups: 1. WubWub 2. Whooosh! 3. Ratatatatata Blagg
I would reduce the mg to half a ton and move it to the left arm. Move lrm ammo to the empty head slot and use the remaining mass for armor. Another variation might be switching to 2x LLas instead of mplas at the cost of the BAP, a reduction of one launcher to a LRM10 and some ammo. The machine guns are kept.