Blessed by the mighty quirks, he shall smite down the unholy! Equip smaller engine if you want more armor.
No joke about the quirks, this variant has an INSANE amount of them, and not very low values either. What's with that?
I've recently started to run a variant of Vergere's "Pumpkin Man" on the Dragon Slayer, which uses a nearly identical build. I've found the combination of MRMs and either LL or LPL to be very effective on Assaults. The range convergence of the weapons is nice, and where the MRMs dish out alot of damage but can be hard to pin-point a certain component with, the LLs/LPLs provide just the right amount of surgical precision to do the job. The builds generally run pretty cool too.
MRM60+LL+ERML is a mainstay in my Atlas D. I considered LPL because their Damage per Tick benefits more from the laser duration quirk, but found extra speed and range worth it over the pulses.
LE300, more cooling. Even more cooling (probably the best variant, due to the fact it has 1080 MRM potential damage with ammo skills)
I think I'll build the last version you posted, it seems very nice to have more cooling and slot efficiency (And still run more than 60 kph, which is fine for an assault/glorified heavy).
I was playing in the mechlab because I was looking for a good mid-long range build before moving back to my actual brawling build... In the end, I made the exact same build I've posted last in this thread, LOL.