I’m thinking about Drew Hayes NPCs and Robert Bevan’s Caverns and Creatures stories, and I realize they have way more tension than most LitRPG novels. I’d like to talk about one reason why. Also side note, I haven’t read Domino Finn’s new book, but from his previous books and his game development experience, I’m curious to see how well he handles the balance curve.
Anyway, in video games in the 90s, the shooter didn’t have instant refills. This meant when you played Doom, if you didn’t play carefully, you’d end up in the next level with no life. This made players search all the hidden corridors looking for health packs and any special weapons to make their lives easier, no achievement needed to make players do this naturally.

Deciding whether it was worth it to replay a level or to go forward if your health was low is a hard decision in older games.
Then came the game that changed all of that, Halo. Halo allowed near instant health regen, so players spend their time jumping up and down and running away from combat when their shield gets low, then reappearing and fighting again. From a game design standpoint, what this caused to happen is that as you progressed, the only variation is more and more enemies.
The game where you can really feel this effect is Bioshock: Infinite. An otherwise great game, but the ending is just ambush after ambush after wave after wave. The reason is that since you can regen easily, the only thing to do is either throw more powerful enemies at you or throw more of them.
This is a standard feature of most regen based games, the mobs just start to grow exponentially as you run around like a madman beating an area. The opposite of this is the Dark Souls style of combat, where timing and strategy beat running and hiding. Though yes, you do a lot of running and hiding from enemies in Dark Souls.
That brings me to most LitRPG novels.

Most LitRPG novels have chosen to use World of Warcraft as their inspiration. World of Warcraft uses the regen system. Wait a while and your health and mana will go up, so you can keep grinding and grinding all day long.
The opposite of this is the traditional gameplay from Dungeons and Dragons. You have certain skills that can be used each encounter, some which can be used only after either a short rest or a long rest, and some that can only be used a certain number of times a day. Because of this, endless mobs would wipe out even an advanced party as they’d run out of heals, spells, and other necessities very quickly.
Since Bevan and Hayes draw from the D&D style rules, the encounters are weightier. Even if you win an encounter, if you used up your best spells and abilities, you’ll be defenseless in the next encounter. This creates more tension in the game as players have to decide what to use and when to use it. This tension simply doesn’t exist in World of Warcraft, you cast away your best spells and use your best attacks as their cooldown goes away.
In World of Warcraft, this is by design since they want you to stay logged in and plugging away, and the only way to beat endless mobs of enemies is by having a recharge based system.
The problem with this is that the tension only lasts as long as the actual battle, there’s no carryover from battle to battle, meaning the only way to increase tension is to increase mob size or power. If the hero just needs to run away for a few minutes to recharge, the battle never has much tension except for the one particular encounter.
The issue quickly becomes a power creep issue, monsters that were imposing early on aren’t even worth considering. In my list of sins two of them deal with this problem. What level am I and How many Powers do I have?
The Warcraft style gameplay is built around grinding, but realistically, most people don’t want to read a book where the hero hunts 100 rats and then 100 wolves and so forth. So they cheat by having a character who gets massive experience while not having any real repercussions around sleeping, getting away from encounters, etc. The hero just bashes all night long and gets fifty levels a book.
The point isn’t that you have to go the Dungeons and Dragons route, but that you should seriously consider what the repercussions of your game/LitRPG decisions have on the difficulty the protagonist encounters. The more limits and tough choices the protagonist has to make, the more impactful the decisions.