I would say it’s the opposite of DCSS in many ways. Like:

• There’s a tight clock named “shock”. Shock increases at a steady rate and the main way to reset it is to move to the next floor. There are some alternative ways but they are either rare (a potion) or have a big drawback (drugs causing addiction). I’m generally not a fan of hunger clocks in roguelikes but IA has a really good one.
• Every encounter can cripple you in a long-term. Taking a big chunk of damage in one turn causes you to gain wounds which can only be removed by expending your medkit uses. So melee leans heavily into resource management. Guns use ammo and throwing weapons are eventually lost. Spirit (local mana) is very limited, takes some time to restore and will kill you if you reach 0. IA is one of the most management-heavy roguelikes out there.
• No auto-explore but levels aren’t as big and you can’t return to previous floors so backtracking is limited. I personally don’t feel a need in auto-explore in IA.
• Enemies don’t give experience. You gain it through exploration and identification of items instead. Stealth is a very viable play style here.
• Experience goes into traits - straightforward upgrades to your character like +10% accuracy with ranged weapons or +1 armor etc. The main form of character progression is through accumulation of items. Potions and guns are particularly important in my experience.

As for how much work it is to play, I find it surprisingly chill. ID game is simple and straightforward, no shops so I don’t need to think about selling anything, no scrolls of enchant thing so I can just equip my current best stuff. You will be primarily occupied with trying to explore as much of the floor as you can before shock and enemies overwhelm you.

My only problem with the game is how it treats saving. The ONLY way you can save is by reaching stairs and choosing to “save and quit” the game. If you choose to proceed to the next floor instead, or if you load up your save after saving and quitting, you will need to beat the new floor until you get a chance to save the game. Quitting in any other way deletes your save file. It sucks.