The game is obviously missing quite a lot of content, but I wanna touch on some issues I had with stuff that is already in the game too.
Teleporters:
The maps in this game already aren't designed rationally, you never really know when one area will lead to another, it's not like exploring a realistic neighborhood or something. This is made far worse by the way the teleporters are handled. A teleporter can be hidden in absolutely any nook and cranny and there are an absurd amount of those in this game. It's extremely easy to burn out searching for them.
Some simple ways to improve those: Make the teleporters glow a bit or make noise so you can see them from around corners slightly. This would prevent the common need to run down a hallway checking every little cubicle/curve for them. You could also increase their size.
Next up: the teleporters could be 2 way, or at least have a receiving end that looks different from the entrance. This gives you a problem that needs to be solved. If you see a receiving end connected to an area you can't reach normally, you know to look around for a teleporter. With the way they just drop you off anywhere, it's more like RNG than a cool puzzle that it could be. Spotting a receiving teleporter and managing to find the entrance to it would give a nice dopamine hit instead of just "Oh, random ass teleporter". It becomes a mini quest that needs to be solved and feels more rewarding for the player to find the way through it.
Enemies:
Swarm basic black monsters: They're fine, they're the mindless fragile swarm zombie type enemy. They're good at filling gaps in other enemies and applying pressure to the player.
Small Robots: Also fine, they can eat an absurd amount of bullets and tempt you into meleeing them, increasing your risk of damage. Their ranged damage is also a moderate threat, especially when in swarms.
Large Robots: Needs an alternate attack, I don't think I was ever struck by one of these. I feel like it'd be pretty cool if they normally guarded their weak point when walking towards you and only unguard it when attacking. For example occasionally they'd stop moving for a bit, unguard their weak point, and charged up/fired a beam at you from their chest/weak point that required you to dodge or shoot them at that point.
Massive black monsters: Again, not sure I was ever struck by one of these. For monsters that seem like they should be a boss, they were never a threat. They need some additional attacks like the large robots. Maybe a ranged attack, or maybe leaping at you from a distance or something. There's a lot of ways to improve them and make them more intimidating, would take a while to go through all those but I'm sure the dev could come up with some stuff if they spent more time on them. They might be in need of a buff/new mechanics the most.
Dogs: They're okay challenge wise, but I feel like they could use alternative attacks too like a lunge after a bit of a pause or something, forcing you to dodge or kill them before they leap. Them just running into you and dealing damage doesn't have much impact. As they are now, they're too similar mechanically to the swarm monsters and need their own identity.
I would love to see more from this dev, I hope they add some missions, more collectables, and a notice of how many collectables you've already grabbed in an area. The map is a bit too large/mazey to just leave it to random exploration for everything without any hints. Though they did space out the costumes evenly/logically. Even the ones I didn't find in my initial playthrough were in the areas I figured they were (So I can't fault them for that, though I can fault them for the massive burn out of being forced to check every single inch of the map for fucking teleporters until I stopped wanting to look for shit, lol).