The LG change was to allow civilians to better contribute to LG worlds and make the AI better at building up LG worlds.
I guess I don't understand.
Civvies already contribute to LG worlds just like normal worlds.
When space is available for colonists, they will move them there.
They are constrained by availability of infrastructure, just like they are with any other trade good.
You can always build your own LGI and give the civvies contracts to move it. They treat it the same as any other contract.
It's just that regular infra is available as a trade good in large numbers from the very start of the game, and is demanded immediately, and more or less inexhaustibly, by all of your colonies (until you tell them to stop or they reach their population capacity).
The fact that LG colonies can't benefit from that source of free infra is a feature, not a flaw.
The gradual creation of a large LG colony is a worthwhile long-term megaproject, on par with de-centralizing production or turning Luna into a galactic banking center or turning Mars into your primary ground force training colony.
If LG colonies merely need twice as much regular infra, instead of their own kind of infra, then LG colonies start to seem barely different from regular colonies at all.