In the end I opted for the solid and reliable Rupture over the fast and deadly Stabber. The "hit and run specialist" Stabber does look like a lot of fun but having been stuck with frigates and destroyers for a long time I wanted to experiment with something beefier for a change.
I haven't quite cracked the rupture fit out yet. It has an abundance of low slots which suggest armour tanking (armour tanking modules all require low slots). Yet I struggle to get a decent defence rating from an armour tank. Amour repairers just don't seem to repair as quickly as shield repairers and there are no equivalents of the shield boost amplifier modules which speed up the rate of shield repairers even further. So I return to shield tanking and even though this is limited by the Ruptures lack of mid slots (only 3) I still manage to get a better result than with armour tanking.
I doing level 2's to increase my faction standing to the point where I can access a decent level 3 agent. Decent in this case meaning an agent in safe high security space who is not half way across the galaxy from my current home port. Given that I was comfortably doing level 2's in a destroyer it is no surprise that the bigger rupture makes them even easier. I have settled on the following passive shield tank configuration using cheap tech 1 modules (click to enlarge):
The key to this setup is the two large Azeotropic shield extenders in the mid slots which increase the ruptures shields from a base of 1876 to to 7050 hit points. The Rupture has only three mid slots and with one filled with an afterburner there is no room for shield hardeners but with over 7000 shield points you can survive anything a level 2 throws at you for a long time even without hardeners.
My low slots support the passive shield tank. Damage Control increases the defence of shield, armour and hull - a nice insurance policy. The Shield Power Relays increase shield recharge at the expense of cap recharge. With three of them I can tank a sustained 53dps (uniform damage distribution) while my capacitor recharge rate is still enough to supply all my needs. The overdrive injector is a bit of a luxury but I like being the fastest thing on the map. Not only does it speed up getting around but I find it is easier to set up and hold the correct aggro pattern when you are faster than the things you are shooting at. Level 2's have lots of 550m/s frigates and the over drive injector increases my afterburner enabled speed from 523 m/s to 610 m/s at the expense of some cargo space.
Most level 2 missions have massed fleets of frigates and I found that with my low weapons skills I can't even hit a frigate with a cruiser sized medium turret. Therefore I have opted for frigate sized small artillery turrets. Add this to my low weapons skills and the fact that I have filled my low slots with defensive modules instead of weapons upgrades and the net result is a pathetically low 80 DPS. Ruptures I have seen on the internet have 300+ DPS but 80dps is enough to kill most of the stuff found in a level 2. I found that I couldn't kill the tech 2 Arch-Gistum cruisers in the Recon mision (you don't have to kill them - you just run to the gate). I guess when I get to level 3's I will have to try and up my offence somewhat.
Not an optimised fitting by any means but it certainly makes level 2 missions easy. In most missions you can tank whatever damage they throw at you. On a couple of occasions I was distracted from the PC so I just grabbed aggro, released drones and let them kill stuff while I was off doing something else. There are a few level 2's with high incoming DPS though (Damsel in Distress and Recon come to mind) so I don't recommend AFK missioning as general principle :)