My thoughts from mechs on your list I've piloted:
SUPER EFFECTIVE!
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QKD-5K
I don't like the chassis, but this thing is fantastic with 3x LL. I prefer it to 4 to ignore ghost heat and have higher up-time when you end up in closer range.
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HBK-4SP
A really solid mech, but you need to use missiles too. Having 4/5 of your weapons low-mounted and on your arms is asking for trouble. But with a good laser/SRM mix, this mech can still get work done post-clans.
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BLR-1G
The only reason this mech isn't more popular is because of better assault chassis that can run pulse laser boats (see Banshee and Zeus). If you rely on torso twist a lot though, be warned it's pretty limited. Otherwise it's a beast in the hands of a player good at positioning.
Solid Mechs
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LCT-1E
Does really well boating ML in my experience. I find 5x with an extra DHS works best, since it runs hot. A good poking mech with much higher alpha than the 1V. Only held back by how fragile it is.
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RVN-4X
I haven't quite hit my stride with this mech, but it's pretty scary if you can master the positioning. I run 2 LPL poke build. The only problem is you have to run a sub-max engine to do it which cuts into your ability to avoid danger.
Good Fun, but more fun than good
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LVT-1V
I almost put this one tier higher. It has the potential to do really well, but more often than not you don't get significant numbers. Still, this thing is an amazing long range harasser with ER LL.
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SDR-5V
The jump jets on this are absolutely hilarious. But in a world of Firestarters and Stormcrows, 2 MPL, no matter hard quirked, aren't enough. Absolute joy to pilot though.
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CN9-AL
I really love this mech and chassis, but the durability just doesn't matter the way it used to. Still, this is really fun to run around with 3 larges. If you want an alternative see the Quickdraw where JJ and not losing 2 weapons with 1 arm make a world of difference.
Meh
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PNT-8Z
(WARNING: I have only played this very briefly on the test realm, these are initial impressions)
It just feels awkward. You lose all your weapons to 1 arm destroyed, 3 LL is too hot, 2 LL is... why not a raven with harder to hit arms? And 3 MPL is just not that impressive.
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TBT-5J
You've got fairly large arms and durable torso hitboxes. This means you will almost always lose your weapons well before you die.
Other Stuff!
These have sub-20% duration quirks, but are worth considering if you like low duration laser builds:
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HBK-4J
More lasers and better placement than the 4SP, better laser quirks than the 4P (seriously, look at them), and without missiles it has no easy to hit hunch. It also has nasty missile quirks to allow a huge variety of builds. My all time favorite mech.
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TDR-5SS
Wait, there's no duration quirks? Nope, but seeing as you're running IS MPL, it's already lower than many quirked ML and LL builds. Also this is inarguably one of the best IS mechs in the game. Your hitboxes are crap, but you should win a 1v1 close range fight with any mech in the game except maybe an SPL Executioner.
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BNC-3M and ZEU-9S
I can't not highlight these with only 1 other assault in my post. These both make spectacular pulse laser boats (hence inclusion in your duration post). They're extremely similar. It's mainly a choice between speed and 1-sided weapons (Zeus) and firepower with evenly spread weapons (Banshee), otherwise thanks to the Zeus' armor quirks they're nearly identical.
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FS9-A and FS9-S
Also mentioning these because they're just amazing at SPL and MPL respectively and represent great knife fighters, which the original list has none of (locusts are just too fragile to do what FS do).