I have done around 200 Test Runs on Sisi with a max-DPS Stormbringer (aka everything blinged to the death with Drugs and Overheat and whatnot). Still there were Death-Pockets.
3 Overseer pockets: death
2 Overseers / 1 Karen: death
1 Overseer / 2 Karen: death
3 Karen: doable if you are not dampened/webbed too much and can start shooting the BS with HighDPS ammo very early
Maybe there are better pilots out there than me but I don’t think T6 is doable reliably in this ship because at some point you will face a combination of pockets that will make you run out of time.
What you can do is starting one Run 19minutes before Downtime each day. If you complete it, fine. If you are going to run out of time, DT will save you.
Also you can make good money by rushing T4s. They complete very very fast and you survive even the 3BS-combos in the worst case. But on average you complete 6-8 sites per hour, which is almost twice what most other ships can do and you don’t even need an expensive implantset for it.
Pyrolancea boosters don’t work for Vorton Projectors, because they are neither turrets nor launchers.
You can’t increase DPS the traditional way on a Stormbringer (or Skybreaker/Thunderchild), because there are no implants, no boosters, no mutaplasmids etc…
The most important factor is piloting and clever choice of targets.
Drag the fight away from anything that can soak up shots that would be better placed on opponents. Like your MTU or NPC-Towers. Every arc that hits those is wasted.
Dont let them orbit you because the NPCs which are currently on opposing sides of you are outside of each others chain-range. Fly away from the bulk and let them all follow you, which will clump them together.
Keep as much targets alive but damaged for as long as possible, so always lock up and shoot the highest HP-targets first and switch targets if your primary goes too low. Your main goal is to produce as many arcs as possible, basically killing all enemies at the same time, not one after each other.
Unfortunately these tips only help in optimizing run-times, but they cannot solve the problem of having 1 high-HP target in the pocket like an Overseer or Karen. Even with overheat there is simply not enough time to bring them down if you get an unlucky chain of 3 pockets with them in a row.
Which basically means when using this ship for T6, you WILL lose it at some point (unless you use the 1-run-before-downtime strat). And since the ship+clone is quite costly, its hardly profitable in the long run.