It occurred to me that the general Space Elevator would quickly become obsolete as improved spaceflight and lift technology becomes more advanced. That, and they would pose a risk to the planet below if the anchor station or support line were severed by an enemy. Here's my thoughts on how to make the Space Elevators, and equivalents, more worthwhile by providing a development path for them.

1. Space Elevator - Add two parasite fighters that would be docked at the space elevator's anchor station. They would have zero range, no FTL, but provide enough defense to ward off unescorted combat transports.
2. Orbital Transport Station - "With advances in lift and spaceflight technology the traditional space elevator has become obsolete and replaced by a series of transport shuttles ferrying goods between planetside and the expanded former-anchor for the space elevator." Higher base industrial value. Can be upgraded for more capable defense craft and/or larger transport shuttles to add a small percent bonus to industrial output of a world. My thoughts are that the Station would have two slots that can each be filled with either an additional parasite fighter or a transport.
3. Orbital Transport Network - "With the advent of even greater technology and economic output, the Orbital Transport Station has been expanded to a truly planetary scale, making transit between space and the surface a common occurrence for many people." Expanded industrial base value. Two additional ship slots. Possible additional economic bonus if there is another populated world within the same star system with an Orbital Transport Network.

As a note, the capability of the parasite fighters would improve with each upgrade, though they would never gain any additional range or FTL capability. With a fully upgraded Orbital Transport Network and all slots filled with parasite fighters, it would provide a moderate defense for border worlds. Initial parasite fighters would be the equivalent of tiny ships. Orbital Transport Station would have the equivalent of lighter small ships. The Orbital Transport Network would have parasite ships that are the equivalent of well-equipped and capable small ships.