The first thing I would suggest is for you to answer some self analysis questions about yourself in MWLL.
1.Which weapons are you good with?
2.How good is your piloting? i.e. How well do you maneuver (legs and torso) to spread damage or protect a weakened component? Do you know how to dodge enemy fire such as LRMs, Arrows, MRM volleys, or even LBX alpha strikes from Fafnir's/Madcat Mk2s?
3.Do you know when to retreat and when to pursue?
4.Do you know the mech variants well enough that, upon sighting an enemy mech, you immediately know what variant it is and the best component to aim for to kill it efficiently?
1. I can generally hit best with either beam lasers or AC/UAC's. I enjoy using RAC's also and I tend to be able to hit consistently with them. Sometimes I can put the SRMs out pretty good but just as often I find myself spray and pray shooting them. I tend to use MRM's pretty well. I haven't messed with ATM's hardly at all. I used to love the pulse lasers in MW3 and I find I can keep the MWLL heavy lasers on target decently enough.
2. I'd have to say honestly that my piloting is good. I've been playing MW for a long time and I have a pretty good handle on how it's done. As far as dodging missiles etc... I guess I'd have to say I've gotten lucky from time to time but I'm not aware of any "foolproof" method as such (aside from hiding behind a hill or jumping at the right time of course...). When I say my piloting is good I just mean the controlling of the mech itself. I almost never lose track of my feet and I tend to be able to stay behind or otherwise out of the firing arc of mechs that are slower than I am. I tend to have good situational awareness regarding my terrain surroundings (unless there are a lot of trees which I tend to run into...) but not as good of awareness regarding my enemy surroundings.
3. Depends on my mood

. I tend to be a flanker and I probably go out alone too often.
4. No. Often enough I realize I've taken a glass canon and decided to brawl with it. I tend to choose assets based on what weapons I like to use and I probably don't pay enough attention to it's strengths and weaknesses.
A lot of people mentioned the fact that maybe I won't like the assault class anyway and for sure... I see the point. But often enough they are the right choice, but I don't seem to have the ability to make that choice more often than not.
Sucks that AC10's suck... They're my favorite weapon. Many times I can sling one out to 550-600 yards and hit a moving mech on the first or second shot. I understand they do less damage out there but there's no sense in not doing the damage while I can

. I don't miss too often at 400 yards or less.