Hyperspace Range currently offers little advantage outside of the early game because an enemy can typically assemble a defensive fleet long before your attacking carrier arrives. If Hyperspace Range gave a small increase to fleet speeds with each level, it would make it worth upgrading even in the mid and late game. It seems Terraforming and Manufacturing (and Weapons) seem to be the critical investments mid/late game, leaving little to no reason to research Hyperspace Range.
Range does indeed give a speed boost between warp gates in Proteus. (Although its a little indirect). It always takes 12 hours to jump through a gate, so the further you can jump, the further you can move in 12 hours.
I like to still have higher range, I notice a lot of players neglect their scanning and range at later levels so I take advantage and set up ships to attack behind their front lines forcing them to move ships back while also attacking the front lines from outside the scanning range.
This way my superior range works to my advantage attacking a now defenseless star because he couldn’t see it coming and all his ships are moving to defend a better star farther back.
Doesn’t always work, but when it does, you not only advance, but have also reduced the ships that would be defending.
This works best when you can coordinate attacks with someone else.