Stalkers are just brutal, and you can dead side. You can go LRMs, LL's, PPC's, SRMs with ML's. Very effective, but slower platform. Do not XL it.
Battlemaster have a nice range of quirks to work with on all the variants, but the 400 XL with pulse lasers is just fun as hell chasing down slow mediums. This is one chassis that I just can not stop playing. The 1S may be the best LRM boat in the game for assaults.
Atlas, there is a reason why people say follow the frack'in atlas. structure quirks make them tanky as hell, on top of just being tanky as hell before. Remember, friends don't let friends XL an atlas. You can LRM with an atlas, but except for the S variant, I still like to brawl with it. Hell even with LRMs I like to brawl with it.
victors, need the xl's and play them as heavies with JJ's. you can also fire an LRM 20 out of a 2 tube missile launcher, just for giggles.
King crabs, with the UAC 5's, AC 2's

, AC 20 is a great DAKKA plat form. OR you can chain fire 4 LRM 10's in the one and just bring on the LRM rage!

Also the high mounted laser and missile makes for good brawling or peaking over a ridge.
Zues, well the SRM 18 to the face is nice, but you can also dead side with Dakka or lasers. The 6T is also a great LRM boat. I just wish they left the missile range quirk on it. I loved hitting mechs out to 1225 m. Believe me the WTF factor was working over drive when I hit them.
Mauler, well it is a dakka platform except for the one, that works well with LRMs.
Awesome, some people say the awesome aint awesome. Now they are variant specific quirks to work with, LL's, LRMs and PPC's. You have to use these for the variants and LRMs are hard to beat with this mech. then the rate of fire with PPC's on the one is almost impossible to match.
Banshee, well DAKKA comes to mind, but the one is great with LPL's. It can mount LRMs but mainly just for show.
Finally the highlander. Limited engine size so mobility is harder in a brawl, so this is a more ranged mech. Just waiting for death from above for the highlander burial. Here gauss and LL's PPC's find a nice home. Note some have very nice quirks for LRMs. One evil thing to do is load up some LRM 5's and have LPL's and AC's waiting for people that like to rush the LRM boats. Most of the highlanders can be used for LRMs effectively.
If you get one look at the profile of the mech variant. IF you can match the profile of mechs that you like or are good at playing it is easier picking up a new chassis or weight class. If you like quickdraws, try the victors. The downside is they do need XL engines to preform well and SRM's are more of an after though.on them anyways. Battlemasters may be another chassis that you want to look at, but here some builds are great with the standard engine. Although I still keep one with a 400 XL in it for terrorizing the medium mechs as I chase them down. I would say the Zeus, but this one you would have look at as a trial mech at some point. Remember all mechs can be good, and some just fit you like a glove. I have a few mechs like that, but a few it felt like they found me. Those are the mechs where you can do things that make people step back and just say, how did he do that. One example is me in the griffin 3M. I have people saying that I can do back flips over mechs while firing LRMs at them just to stay 180 m away from them.
Note: all reference to LRMs are by observation either in game or by doing the math. Many opponents have been harmed in the verification of these comments.