From memory, in general:
Lots of chests for pistol of shame as you will be corpse-runningba lot.
Main goal is flamethrowers or death. You have nothing else that can stand up to a prolonged assault hands-off. N O T H I N G
Walls are too expensive - stone smelters cover a larger area and are more efficient for stone cost vs size. Use these at chokes.
Use natural terrain features a lot for chokes, but remember how big spotter range can be when building.
You will want something disposable for early warning, so you can rush to meet waves.
Rush oil, flamethrowers. Defend oil area like your life depends on it, because it does. Iirc we lost a large chunk of the base and rebuilt around oil again, as only the could we erect permanent fortifications.
Once you break the back of early-mid game and start to scale past first rocket, it does turn back into feeling easier, just with lower UPS and wading through swarms of enemies like doomguy.
Definitely renovate it and keeping your code in a bit using gotops principles. When I run k8s I used flux to reconcile my reponstate to my clusters.