This, for me. I've never had any hankering for the big ships anyway, so carriers hold little appeal. And I fully expect a great wailing and rending of garments when the fuel requirements for jumps are announced. At least I hope... if Beagle Point in 130 jumps becomes as trivial as it sounds, I think I might be done with the game.
The 500ly jumps are bound to make the map smaller, however, I suspect that very few will use them for exploration. Why haul one of those fuel gobbling things to far flung places? It can be difficult enough dragging a DBX to some places.
And yes, the jump range will dramatically reduce the amount of jumps but as you say, the inevitable time it will take to gather the required substances will probably mean a balance, you can imagine it will take as much time for one fleet carrier to gather enough substances to make the 500ly jump as it takes one DBX to cover 500ly.
I suspect that most will be used in and around the bubble. Like that bloke walking up and down the road with his violent dog.