My 3L build.... 
RVN-3L "Wulfram"
 
AMS is wasted on the Raven 3L.  Your ECM protects you from most LRMs, AMS doesn't protect against SSRMs, and even if you get tagged or countered you are fast enough to get to cover easily.
 
TAG is great.  Not only for helping LRM boats on your team, but increasing the lock-on speed and decreasing the decay of your SSRMs.  You also get some nice cbill and xp bonuses when using it now.
 
With 2 Medium Pulse Lasers, I find I regularly do more damage than 3 regular MLAS.
You often hit and run, especially now, and the shorter beam duration allows you to better concentrate fire on the target then move away.  Also, the pulse lasers crit better.
 
With DHS, the default 10 in-engine heatsinks are more than enough for 2 MPLAS and 2 SSRMs.
I hardly ever have to watch my heat, even on Caustic.
 
Max armor except for the cockpit, which is reduced to 12.  In hundreds of matches, I've never been killed from a cockpit shot.
 
 
This is what works for me, anyway.  Just some more to think about! 
 
 
 
EDIT:  An alternative if you don't like pulse lasers is to replace them with normal medium lasers, then add another ton of SSRM ammo to the head and another DHS to the engine.
This also helps if you have trouble managing heat and ammo, obviously.
					
					
					
							Edited by Ravennus, 28 January 2013 - 05:18 AM.