hi there i am a fairly new player ~400 matches(?) but i have some anecdotal examples. i started playing with friends and decided i wanted to start with LRMs since i enjoy the damage support playstyle. i was a frost mage in WoW, control wizard in dnd, and generally play heal/control/ dmg characters in other RPG games. for FPS i enjoyed playing the sniper type character Battlefield (2142 was awsome), CoD (maps built to say FU to snipers), World of tanks (SPG so hard but rewarding).
when it comes to MWO i have tried a few different types of styles; backstabber (no thanks), hit and run (ok), flanker (good), fire support (enjoyable!), skirmisher (good). i own a 4 mechs (in order of bought): Mad dog, shadow cat, raven 4x, gargoyle. i wanted one from each weight class, but i know from the trial mechs i don't like being slow.
my current LRM build is Mad dog (mixed omni) 3x LRM 20 (1 left 2 right torso), tag (right arm), 3x HML (left arm) for backup weapon. (shadowcat is a large pulse poker, raven was kinda meh, gargoyle lazer vomit poke/skirmisher LPLx2 HMLx4)
when i started out i bought the mad dog on recommendation of my friends i started using H omni loadout and only LRM 40 (no tag/art), the first thing i noticed was that locks took a "long time" and often locks would disappear right before or after i was able to launch a salvo. i had kinda bad map awareness and would fairly often get left behind as the rest of the team went nascar, pushed ahead, ect. this didn't bother me as a sniper mentality even when i was swarmed by light because if you get caught out as a "sniper" its your fault.
looking at my damage score i was often hovering 300-500 dmg average and learning maps, HPG and Solaris were my "bad maps" because i couldn't contribute much and i noticed more and more how the arc fired getting more and more dmg as i learned to bend shots and figure out if i had a clear line of sight (kinda like the SPG in WoT but homing). started noticing the countermeasures more, Stealth, ECM, AMS; stealth didn't bother me i had teammates who could often deal with them, ECM sucked since it took so much longer to get a lock, but AMS . . . AMS was my honest bane i was noticing how when 1 or even 2 mechs had AMS i could do nearly NO damage or suppression even with LRM 40.
so i started looking into the mechanics of LRMs and specifically AMS. i was honestly supprised to find the disparity between clan and IS LRMs. the stream-fire of clan let AMS take down DOUBLE the number of missiles than IS LRMs. so that means that to AMS i am effectivly running 2/3-1/2 the number of tubes (not actually but how i felt). well lets try something stupid, i tried to see how many tubes i could fit (90 max) then scaled it back considering i KNEW it was stupid idea. 80 was workable but 60 was where i finally felt like i reached a balance, enough to get through most 1-2 AMS mechs but not too stupid for heat/ weight. i had 4 HML for point defence but swapped one out for a tag during this testing phase and i much prefer having a tag than not (though artemis sucks for its costs to me).
within the last month i have increased my average Dmg K/KMDD/D. i am now averaging 7-800 dmg a match, 1-3 kills, 3-6 KMDD, and survive about 25% of my matches. i am more on the front lines than i used to be trying to get that sweet tag lock but usually flanking (who would expect to see me out there) then setting up for my team to come TO me. after learning the maps i only HATE 1 and heavily dislike 1 (solaris sucks, polar is straight up bad!). my fav maps are canyon, frozen, and mining.
including ALL of my early games MDD is @: .89 W/L (just over 200 matches), .72 K/D (~45 more deaths than kills and doesn't count KMDD at all though), 79.5k lifetime damage.
(100 matches is shadowcat, 4 in gargoyle so far, and 26 in raven)
LRMs suck when you are out in the open and hey sometimes you HAVE to get spotted to get a better position, hell i almost was melted on polar when i peaked the domination ridge and got his by multiple LRM boats (pretty sure they were boats with how many) i had red armor on torso, and was orange on CT and LT with heavy armor damage to the rest of my front.
dealing with LRMs is comically easy with a mech faster than ~70kph, you out run the damn things and break lock; seriously! i always run radar dep because i like the playstyle. AMS 1-2 chews through clan LRMs like butter and the IS ones are so spread its a gamble which missiles get targeted (luck if it targets the edge you are running towards (or center if your tanking the hit). ECM is honestly bonkers without tag/narc making it basically mandatory to have one or the other (preferences apply), and stealth well tag and point defense takes care of that. i run pretty cool with 14 DHS as long as i only fire the lasers every so often.
this all being said i think this LRM are OP pls nerf stems from the same fact i have had to deal with in other games, people don't like to deal with things they find unfair/ slow them from doing what they want/ ect. stealth in games where you are litteraly invisible? omg i can't fight them, use AoE! omfg sniping is such a p*ssy way to play the game. well it is there for a reason, if you stand out in the open just shooting then expect to get shot or suppressed (BF2142 was magnificent game! even had mechs), omfg i just got to the fight the artilery is overpowered! i am a SPG i watched you litteraly crawl across the map through open terain and waited for 5 SECONDS holding ABSOLUTLY STILL so that i could have a 1/4 chance of hitting you (WoT painful arty expericnce) with another 60% chance it bounced off your armor.
with how the tabletop played LRMs are actually underpowered (especially due to ghost heat) as are PPCs and Gauss (crit through armor anyone? hell imagine the 2.5 splash dmg from CERPPC hitting components

. the core game is high casualty gameplay, hell you are more likely to hit cockpit in TT than the horrid hitboxes in this game, no melee, no Death From Above. the game is super precise too, a more TT style game would have cones of fire and hope to god you got lucky where you hit within it.