It seems that my base design is most similar to meganoth’s. It relies on giving the zombies no choice but to take a long, winding path to get to me, during which they’re exposed to me shooting at them the entire time. The primary purpose of my base is not to kill the zombies, or to have more block hit points than they can damage in a night, but to slow them down as much as possible. I never leave to chance what path the zombies will take to me, as I’d be doing if I camped out on a POI rooftop.
This base isn't totally finished, but it's far enough along to share.
I access the base via the wooden frames (it will be a drawbridge eventually), which of course I pull up before horde night. With the frames removed and me in the tower, the only way the zombies can approach is to jump down into the pit. There are ladders out of the pit, but they go extra high so that zombies can't use them to go down and avoid taking fall damage (yes, that's what they did before I fixed it). The pit is made deep enough that 'normal' zombies lose a third of their health to fall damage. I want my zombies weakened, so I can get the kills and XP myself.
Then the zombies have a path to me in the tower, not by beating on any walls but by climbing the staircase. It's made of full blocks instead of staircase shapes, because zombies take longer to jump up on blocks. So do I, which is one reason I don't think my design is cheesy. They jump up six blocks, and then run across the flat portion to the next six block staircase. Across each of these flat segments is an electric wire and campfire. I could've made the base without the flat segments, but I opted for this design in order to have room to expand and try different traps (I used barbed wire pre-electricity), and so my sight lines from the tower wouldn't be too steep.
Speaking of which...
This is what horde night looks like for me in first person. I stand in the mostly-enclosed cage just next to the steel vault door that the zombies are ultimately trying to reach. I can shoot them as they run around the edge of the pit deciding where to jump in, and I can shoot the ones that have fallen in and are slowly making their way up. The open switchback design works even better than I'd hoped, because sometimes they overshoot the last jump of six and fall to the bottom again. Meanwhile I'm killing most of them before they get close. One corner of the cage is open so I can throw down molotovs, my explosive of choice because it doesn't do block damage. I've also recently installed an SMG turret on the outer wall, connected to a switch to shoot them in the back (hopefully not detonating demolishers) if things get hairy.
The design is symmetrical, with the same staircase etc. on the east and west sides. Each side has a steel vault door, and outside of that an iron hatch. I can raise the hatch at any time to redirect the zombies to the other side. This way, even if something catastrophic happens, e.g. a demolisher blows up and takes out a staircase, I can shift the zombies to the other side. They still have a planned path up, so they still don't attack the bottom of the tower, and hopefully that gets me through until morning when I can repair the damaged side. The base is on 8 pillars of reinforced concrete, 4 of which go down to bedrock, and I intend to eventually fill it in to be a solid core of steel. But that's a just in case thing. This base is more finesse than brute force.
I wanted this base to prove a few things. I wanted to show that you can have a 'real', plausible base that doesn't rely on some cheesy one-off shape that the AI can't navigate and will probably be patched out later. I wanted a base that offered protection, without doing all the killing for me. I wanted to show that you don't have to have a horde base separate from where you live, or sacrifice a POI every week. You can have one base that you both live in and fight in. The floors below the top floor of the tower have all my stations, supplies, and my bed. I even went with the ill-advised rooftop garden, to drive home that you can have everything at a single site.
Because of this, I am not stranded on horde night. I am one with my base. If I need to go downstairs for a moment and get some pills to cure that concussion, I can. I can stay safe for a long time inside (the zombies have never even reached the vault door). But at the same time, it's not an AFK base, either. The base doesn't kill hardly anything, unless I hit the panic button and turn on the turret(s). It's up to me to get the kills.
The pitfalls (ha!) of this base have been:
Lots of digging up front. At least it was a lot for me, but then again people dig down to bedrock. I planned out exactly how to create the pit with the optimal amount of dynamite. If you do the edges first to create a moat, then you have something to withstand a horde night or two while the base is under construction. That is, you can stand in the middle island of land that you'll eventually remove anyway, and let the Blood Moon zombies do some of the work for you!
There's no scenic view from the inside. I chose a base site with a nice view and put in lots of windows but, even though the pit is big enough you don't feel like you're in a cave, you spend your in-base time looking out at the concrete walls of the pit and stairs instead of whatever view you'd have.
It's not a good design for close ranged weapons. I planned on specializing in shotguns since I've been doing a strength build, but it turns out the range on shotguns sucks. Like, if a zombie is just ten meters away, I'm using a full clip of pump shotgun rounds to kill it because the damage falloff is crazy. You can let them get closer, but then you're wasting the valuable space and time the design gives you when they're tied up in the traps farther down. You have less buffer.
It doesn't fail very gracefully, with the single exit point. If zombies were to breach a door, it'd be difficult to get past them to the drawbridge, very difficult when the drawbridge is still a row of wooden frames, and very difficult & painful if neither is an option and I'm forced to get down in the pit to one of the ladders. I should probably do some sort of fire escape to get to the surface without letting the zombies jump in the same way.
I laugh when people say there's only one way to play, now or ever. This is the first time I’ve used this particular design, and the third different base I’ve constructed during this long A19 playthrough. I’ve also tried running away on a vehicle, out of necessity. And while it’s not easy street, it’s not "forbidden" either, and neither are underground bases "no longer an option." If TFP really wanted to forbid these things, they'd have listened to the suggestions of some, and made vehicles not work on horde night, or turned stone into bedrock. But they didn't do that. They didn't remove gameplay, they added gameplay in the forms of vehicle-chasing vultures and digging zombies. Not because some horde night strategies were 'wrong,' but because the difficulty wasn't comparable to other strategies whose designs are more developed.