After some serious thought on the matter, I have to admit; I've had a change of heart.
I no longer think increasing flak clip size is the best way to go. It just takes too much fun away from the gun. That super high risk high reward, only two shots and you better make them mentality, the visual of watching the first shot literally bend and twist the enemy ship and the second shot smashing it to pieces is too awesome to give up. The Flak gun for me was always the most satisfying gun to use, a giant cannon that only did one thing, but it did it well.
Emotions aside here's some balancing reasoning to back this up. With a 4 shot Flak cannon you get into a bit of a pickle: Either lesmok will be way too weak (the current problem) or burst will be way too strong (people's deepest fears).
My proposed solution is quite simple. I think the simplest way to buff the gun is to, well just buff the gun (stay with me here now).
The problem with lesmok as it stands is that it's just too weak. If you hit someone with it; there's a good chance they'll still be charging in at you and kill you while you're in arm time. I think the way to fix this and to fix the gun in general is two fold:
1) Increase the lifespan of the shot, so that vanilla rounds travel farther. I think this is something most people agree would be good for the gun. Anyone that can hit at 1.4km on time and on hull with vanilla rounds twice deserves the kill.
2) Increase the overall damage of the gun, but backload it onto the aoe damage, not impact. Instead of 147 impact and 148 aoe, change the damage to 147 and 243.
Here's why this helps: By upping the damage of the aoe, a lesmok shot goes from doing 400 pure hull damage outside of arm to 546. With this change lesmok will make it so even though you don't kill most ships (other than a Junker providing you can hit it) you'll be able to severely cripple them so that you or your ally can finish them off much more easily if they enter arm time. This will also change the flak from a very high risk high reward weapon to a high risk high reward weapon since even though you won't be able to one shot kill; you'll get a lot more bang for your buck if you only make one shot.
Now for all you that are still suffering trauma from the claiming the Fjords tournament, here's why this is still balanced: Heavy flak, prior to 1.31 was always able to two shot kill ships and one shot kill Junkers with charged rounds or almost with a buffed lesmok gun and was by no means considered op. It still won't be able to two shot a goldfish or a galleon. Even more importantly, getting within arm time will still allow the same amount of safety as before due to all of the damage increase being back loaded on aoe damage therefore not being active withing arm time.
TL;DR Heavy Flaks with two shots are more fun and easier to balance.
Increase the range vanilla rounds can travel to give highly skilled gunners a chance to make mid range kills.
Increase aoe damage without imbalancing the gun so long range lesmok shots are meaningful and mid range shots give a greater reward if shots are missed.
awkm - would we be able to test these changes (also I didn't include it here but could we do it with the old arming time?)