Sorry, bro, and I feel your pain.
I was in a bit of a slump a while back.
Thing is with Hawken, there's SO much to focus on.
Buying new mechs.
Ranking them up.
Making HC credits, to buy items and internals.
Finding new players.
Testing new mechs, trying different fighting styles.
But, through this, I wasn't happy with my mouse setting. I'm used to high sensetivity, and usually don't like mouse acceleration.
But, after a bad few rounds, I made up my mind, before I DO ANYTHING else in this game, I'm gonna get comfortable and happy with my hardware.
So I spent a day, just tweaking my mouse, and discovered a few changes REALLY improved things for me. I keep my DPI around 2200 - 2500, and turned down my in-game mouse sensetivity from 90-100, down to 40 or 50. Then I went back, and added mouse acceleration from 0, to about 2-3.
This let me have decent mouselook at close range, and a slow, steady hand at long range.
I STILL could tweak it a bit.
If you're not happy with Flak, (I'll confess, of all the weapon types, FLAK is my .... most DIFFICULT to master. I believe THAT comes down to a lack of comfort, or harmony with your mouse, in being able to track, anticipate, and LEAD your enemy.) Just try different styles of weapons. enjoy messing with rockets, blasting with heat cannons, etc.
Don't focus TOO much on any one area of the game, just try different things out. But I believe, your mastery of the Flak will come, as you fine tune your mouse settings. Also, take some time, work on your strafing, and your strafe boosting. Put Air Compressors on ALL your mechs, force yourself into air acrobatics, as a matter of discipline.
And play a bit of Co-op TDM or Bot Destruction, just to have a bit of fun. You can cuss the robots out without their feelings getting hurt!
Hope this helps. Be positive on the battlefield. Encourage new players, compliment good players, even opponents. Trash talk players with dumb mistakes, (shooting guns at battleships, not taking the AA zone!), and being on this Forum is a great way to see who'se out there.
Hope that helped, and Good Gaming!