I'm quite surprised nobody thought about this build, but that's probably because it's not easy to drop with an XL bushwacker, especially if it is fitted for brawls. Anyway, use this bushwacker in either scout or quickplay where/when a brawl is expected and there is no chance enemy will bring long range weaponry. Use 3 weapon groups: Arm mounted 1xSRM6+A Torso mounted 4xSRM6+A Chain fire 5xSRM6+A Leave arm-lock turned off, so you can torso twist, fire the 1st arm mounted SRM6 followed by the remaining alpha strike of 4xSRM6. Due to recent increase to SRM ghost heat, NEVER alpha strike with this build. Use chain fire instead when running hot. Ammo is positioned because focused fire on legs is expected. Change position if you don't feel comfortable to keep ammo in torsoes. Don't forget you have artemis, so you don't have to hug an opponent to have decent focused damage: move back to cover and poke if you are being focused. Skill tree should be the classic focus on firepower, survivability, at least half radar deprivation, maybe full seismic, coolshots and air strike if you really like it and have nodes to spare.
I like the fact that you have a main BLAAAARGHST of missiles, and one arm-mounted SRM to aim and finish off remaining components. How is this compared to the 4SRM6+A with lasers and MG backup?
Honestly, I've never bothered with MGs because you have to face tank the whole time, so you can't force your opponent to spread or focus damage. I've also never bothered with lasers because you can't boat them, so they feel quite underwhelming.