Don't see how it's practical long-term
There's just too many scenario's where a single Gorge can lock down a corridor to the point that it's impossible for two marines to break and where two Gorges can lock down a corridor to the point that it's impossible to break without GL's at which point a single Whip makes it impossible to break without ARC's.
This kind of Static Defense is easily established within the first one-two minutes with competent gorges and far positions and on maps that only have a few lanes this shuts down a lot of Marine expansion and leaves any open area to be better focused by skulks.
You might argue that a single gorge is easily overwhelmed, a single marine with less than perfect aim can't kill a healspraying Gorge before it (plus hydra DPS) kills him and if a group of people are coming the Gorge can run before they try to get past the Hydras. If the Hydras fall he can replace them for free.
If the marines focus the hydras from range by a couple marines they can be rebuilt faster than they are killed. Now that's just a single gorge acting alone requiring a focused effort to kill for the cost of 10 pres for him..
Two gorges is impossible to break without GL's and like I said that becomes a problem when a Whip is put down.
Maybe this only happens with bad marines, but I pushed North Tunnel with another Gorge to the Marine WH start and there was nothing they could do about it.
Second hive comes up relatively quickly and suddenly you have half the routes on the map locked out by Hydras.
The Gorge is survivable enough, Hydras are incredibly easy to make and several times harder to kill and if there is too many of them they requiring end-game tech from the Marines to break first second tech from Aliens.
It simply doesn't make any sense, I have no problem with Cysts remaining free or Clogs - But, having Hydras for free is just ridiculous.
Honestly I didn't think much of it (I had assumed developers would realize the obvious mistake), it was only when I saw in the development thread that they planned on having Structures made by people who Gorge then switch out disappearing over time as if this would solve everything and without it is balanced - Which it is not.
If this game wants to release in a few months the developers need to work on balance. The only place where they had a similar mechanic like this was in Combat Mode NS1 and that was because everyone spawned with upgrades.
But, if you can convince me that this is better than the PRes system and that having Gorges sat around with 90 PRes makes sense I'd be glad of the counsel.
So please let me know what you think about the new building changes.