There seems to be a lot of bickering about how tradelanes should work but I have seen no functional suggestions so here goes:

Assuming we already have the following:
1) regular thrust [speed x1] (weapons and maneuvering thrusters available)
2) Cruise drive [speed x3] (takes 10 seconds to engage, no weapons or maneuvering thrusters)
3) Tradelanes [speed x 10] (see below)
4) Jump Gates [wormhole speed] (travel to another star system)

The problem with the MS Freelancer game was that physical rings cannot align in space where objects are always in motion orbiting around something.

My solution: Remember the StarTrek episode where an alien race developed a "wave" for spaceships to ride on to their destination?
Both Point of origin and destination will have a "Wave generator" in orbit that keep themselves aligned - that means they need to point at eachother with clear line of sight. This way only two physical items need to be build and maintained. Each Wave generator will consist of two rings (thus looking similar to the Freelancer device) one ring to launch, and the other to receive incoming traffic. However, as the wave generator orbits the planet it will at times lose its line-of-sight with its counterpart when the planet itself gets in the way - Hence each tradelane will have regular downtime when the link between the two points is lost. To minimize that from happening each wave generator will be placed in very high orbit. When the link is lost, ships will have to wait (no more than 15 minutes) while ships already enroute will continue on their perspective wave. Should anything block the wave from reaching the destination then an audible alert will warn the pilot to abort and break away from the wave before collision (Pirate tactic?). A ship crossing a tradelane could sustain heavy damage from collision and thus tradelanes are easily detected by any ship using basic onboard sensors (on the notion that both wave generators keep in touch by a direct data-link). If the conflict is with a planet or moon then the wave would not harm anything on the surface (the energy moves through matter).

Q&A:
--> Will it cost money to use? Yes, each use of the lane will incur a charge.
--> Will it save you fuel? Yes, while you ride the wave your engines will be at idle.
--> Can I get a monthly pass for unlimited use? Yes, purchased from the tradelane owner - that would normally be the ruling government.
--> Can I build my own tradelane? Yes, you may order a tradelane to be constructed from a POI that you own.
*However, to avoid too many tradelanes in the game, each order must be submitted to and approved by SC.