So here is my current config:
IV-FOUR

Slightly altered the stock layout:
XL255, 2x UAC5, 2x SRM4, 3xML and more armor.
So far I had some luck with my first matches (k/d of 10 in 3 matches, 6 kills in 3. match, wheeee) and this seems to be a good brawler, even with the slow speed.
There are potentiallly 2 tons available if you drop the sinks, more ammo for the Ultras would be really helpful or pumping up the engine a bit. Even with the normal AC5s you get through 90 rounds pretty fast so maybe just more ammo.
No LBX version yet because I like those missile backup. gets really helpful when you're out of ballistics.