There's no real use for a carrier for an explorer.
I mean, at the moment you travel from system to system. You scoop some fuel, you move on. With a carrier, while you can cover a bigger distance per jump, you'll then quite certainly require much more time to collect the fuel again.
All in all, without anybody here knowing the final numbers, I would very much expect that you can travel the same 500 LY faster by just jumping and scooping than by collecting fuel for a carrier. And on the normal exploration route you go through more systems, increasing your chance that you see something interesting.
The only thing where the huge jump range could be of use is if you specialize in exploring systems at the galaxies edge, which can not be reached by a normal ships jump range.
Of course that's just based on the information we have up to now. Perhaps some of the modules change everything and we just don't know that yet. But I kind of doubt that. Thus I also don't see any point of such a ship for a casual mix-and-match-style player like me. Time will tell.