Aside from the obvious overpowering of the Scar (75% of all kills are done by the Scar), i went to play with a few other weapons.
most notable the L-TAG. a fun and interesting weapon. it fires grenades. given how crazily powerful grenades are (at full armor, i get killed by nades from 5 meters away), the Ltag with it's 15 or so nades should be absolutely owning.
it's not. far from it. although i had some moments in which i had a triple kill, my KD with an L-tag is always negative. mostly about 10k/12D. compare: Scarab gives me about 14/8, DSG about 8/3. yes my KD is mostly positive.
the GAPING flaw in the L-tag is that it isn't designed to work at the optimum ranges.
in Crysis 2, there generally are 3 distances at which you play. namely melee distance, the 10-20 meter sweetspot and the long distance (about 50 meters) sweetspot.
the L-tag nades do not explode for at least 10 meters. so you say, "exactly in the mid-range sweetspot". well, no.
the natural reaction to an L-tag is making a single jump forward. the L-tag nades simply don't detonate on you and they slid past the enemy, harmless.
this makes the L-tag somewhat... useless. most people simply jump/run into the minimum range of the L-tag and kill you in no-time. add the obvious grenade trail to it, and you are an easy target.
add to that, that the L-tag also is severely affected by gravity, which makes aiming not very precise.
the JAW suffers the same fate, with the main difference being that the JAW is absolutely owning when it hits, but at short distances, it won't detonate. which means going out with a flare won't work. not even at a distance at which it would mildly damage you and kill the enemy.
VERDICT:
both the L-tag and the JAW need a smaller minimum distance, otherwise they are simply useless