Don't know if this is a build already discovered, but I built it in smurfy and tested it tonight with outstanding results. Weapon groupings: 1] ERPPC 2] Tag 3] LRM15x2 4] SSRM2x3 + MLx3 (the brawler combo) Benefits: ERPPC to disrupt ECM if beyond 750m decent heat management if you don't go crazy strong brawling punch with 3x medium lasers and 3x SSRM2's. Shreds lights in seconds still maintains LRM30 long range support including TAG for additional team support (and tons of support c-bills/xp) Tag and ERPPC located in top of mech; easy to peek over hills/ledges to tag for missiles or PPC snipe Cons: uses an XL engine. Spreading damage is recommended (torso twist) slightly low on LRM ammo count but PPC helps to fill in dps between missile salvos I tried every 5M and 3F combo I found on here and in the official forums, but was also frustrated at 2 things; not being able to counter ECM beyond 750m and lacking close quarters combat power. 3 streaks and 3 medium lasers are more then sufficient to deal with anything that gets too close. Depending on the map you can throw in some ERPPC shots too if you see a critical component on your opponent. Even on Terra Therma, you can maintain constant LRM15 chain fire with ERPPC shots mixed in. If the target gets too close (or an unfortunate light thinks you're an easy target) the 270m range weaponry shreds. I really tried to fit a BAP in but without sacrificing more armor it's not possible. I also tried to make this work for the 3F/3F-C, but it ends up being 4x MLas and 2x SSRM2.
Drop the ERPPC to a standard PPC, and you'll still get that ability to knock-off ECM up to 1000 meters (i.e. maximum LRM range), while at the same time greatly improving your overall heat efficiency. And considering that you have Streaks and MLasers for CQB, the 90 meter minimum range on the PPC shouldn't be a problem at all. And yeah, like Blagg said, drop that engine to an XL300, and you'll be able to pop a BAP in like you wanted, as well as add another half ton of armor to the legs.
I shall not compromise my standards! Interesting build though. The PPC is nice and handy but not necessary. I find it hard to justify the sacrifices to add a weapon system designed solely for DDCs in the 750-1000m range, a very niche situation. Besides LRMs work best as a midrange weapon anyway due to flight time. I like being alive and having more ammo
Thanks for the replies. I actually abandoned this one in favor of another build which I'm going to post after this.