itch.io

I like the way RE balances difficulty. Enemies are always difficult to put down/evade, but the difficulty setting tweaks some basic variables, like enemy damage output, and how many items/enemies appear in each room. So on very easy, you can take a lot of abuse (something like 6-8 grabs), there's fewer enemies per room, and healing items/ammo are abundant, while on hard, you can die in 2-3 grabs, healing items and ammo are few and far between (yet still abundant enough for a surplus by the end if you play your cards right), and there are a lot more enemies roaming around. You might also notice level design-wise that the game has lots of narrow corridors to force you to get close to zombies. Or one of my favorite examples in the RE1 remake: making you walk right next to the giant shark that just lunged at you, to pick up a key. A similar mechanic in your game would work wonders--something that forces the player to get uncomfortable to make progress. Imagine, for example, having to jam a hydraulic press with a rickety piece of junk (let's say it's a steam punk style machine and you're jamming the object into the gear assembly) to crawl through it, all the while you can hear the gears chewing away at it. And then having to crawl back through it only for the gears to win the battle just as you cover the last inch. Maybe even make a cutscene out of it. The protagonist jams it in a couple times, the gears spit it out, and when it finally sticks, she says something like "I don't know about this...". That would be nerve wracking and memorable!

Just spitballing ideas ;)

I hope the dev cycle goes well for you, man.