I also think that the Type 6 is a good choice for exploration. Upgraded the FDS, PP, thrusters etc. to A* the ship has a jump range between 25 and 27 ly depending how empty your fuel tank is. I'm currently 2000 ly away from SOL and the jump range is still high enough.
My only concern with the Hauler is it's speed. It's one of the slower ships in the game. Since I fly with no weapons or shields, evasion is paramount. I'd rather sacrifice some FSD range for the speed. Even my optimized Sidewinder that I currently fly does 12+ly jumps and that's not even with the best FSD available. There seems to be plenty to explore even with that jump range. I may just keep upgrading my Sidewinder. Then eventually get a Cobra for the speed.
This is what I've found too. The Cobra is fine for anything within 15,000 LYS. I squeezed a 29,000 LY trip out of a 25LY-capable Cobra but it was a complete chore at times looking for routes across sectors full of brown dwarfs and crossing interarm voids that have lower star density - never again!.. beyond that you really need a 35.5LY capable Asp with field maintenace units packed in the internal slots as you will have the odd fuel scooping accident from time to time. And with the new wear & tear feature it can subtly creep up on you. I have 3 fitted to my ship and have exhausted one already.