T3d would be best because then you can just use an active tanked pvp fit and be fully ready for a pvp engagement.
If you’re alpha I would either keep it really cheap and expect to die or keep it kitey and fast and avoid entanglements. If you kite, DPS will be your biggest challenge.
The problem with using a destroyer for this activity is if you come across a clone soldier, you will probably not be able to kill it, and that will be disappointing. You might have the dps but certainly not the tank. They can actually track and hit little things and project their damage a bit more than your average rat.
I can also tell you that if I saw a destroyer ratting in one of the lowsec systems I frequent, I’d eat it like a piece of chocolate. So don’t make it easy. If you brawl you’ll be a sitting duck. Kite, keep moving if you can!
If you want a ship that will be really successful at this I’d recommend the worm. You can easily do 300 dps at range with a worm and keep it above 2kms, aside from when you need to loot. You could use a 100% pvp fit and make it work.
In any case I would look for ships that can rat in a pvp fit. Don’t use a PVE fit and expect it to go well when ■■■■ hits the fan.
One more thing; you can find empty systems to do this in and be pretty safe. Don’t make the mistake that many players do which is ratting in an entry system. Go a little deeper. If you rat with anyone in local at all use a local checker tool such as https://localthreat.xyz/ I would try the big, empty, non-FW regions like Aridia, Genesis, south Placid, east Derelik. Stay the hell away from Black Rise and the like.