Regular L-3 is really good and definitely better than the L-3D one, though L3-D is easier to use because of it's kit. Managed to get to S+ with the L-3 the other day and I can see this thing being high tier, just falling short against the top tiers. Great weapon overall and amazing kit. Really, the only thing that's lacking is more range to fight the longer ranged weapons like the 96 gal and sspro, and it doesn't have anything abusive, except maybe the disruptor into wail combo, but you can't really spam that so not really.
Kinda funny that when the L-3 first got released, I thought it was garbage because of how hard it was for at the time. I gave it several tries and still hated it, then recently I can finally aim with this thing so could finally started putting in work.
For my gear setup, I just stack lots of walk speed and ink recovery while still using cold blooded and ink resistance. My current setup has 1 main, 2 subs for run speed and 4 ink recovery subs. I might try using some bomb range for my disruptors tho. Ideally, something like 1 main bomb range, 5-6 run speed subs, and the remaining for ink recovery sounds ideal to me.