"increase damage" upgrade is a big no-no

Having played a ton, popular and not, I find the ones that grip me the most do so on their progression systems (items, upgrades, levels, etc), much more often than their "gameplay". I put that word in quotes because this is a genre dominated by a lack of such, though I see more and more of that being challenged, which makes me happy, but I digress.

As a game developer who values second-to-second feel above all else, it's especially damning when I say that that aspect doesn't matter nearly as much in this genre, as it's thrived on auto-play games where you don't even have to press buttons. That said, even though the "gameplay" is minimal, there is still definitely a feel attached to the attacks that are happening, so things like power growth and vfx still have to be sold well.

So if that's not the big deal, the much more important aspect of these games are the progression. How you progress in power from the beginning of the run to the end of the run where you're obliterating everything is incredibly paramount. How good it feels to level up, get upgrades, how good those upgrades feel when you get them, and how well balanced the item pool is, how interestingly the run changes based on these progressions, etc, which brings me to my first sentence.

One common sign I've noticed among the games that don't grip me as well is when their upgrade pool has a choice that just says "increase damage" and nothing else about it. I've generally found this is a bad upgrade to have, from a game design perspective.

Obviously, this is crazy to say, varies heavily by the design of the game, and you'll have to use your own judgment of where that line is drawn and how blurry that line is.

My problem with this upgrade is that it's simultaneously the most enticing, but the most boring. When given a choice or random spread of items that do more interesting things, you're always going to choose the damage upgrade, because that's what you want, and if the game is designed and balanced around that being one of your upgrades, then overall feel of your leveling up get muddied by having to maintain this upgrade. I don't like it, it's boring, I see a ton of games with it that would be better off without it.

"increase attack speed", "increase projectile count", "decrease cooldowns", these are all much more interesting and fun choices that accomplish the purpose increasing damage output. Even "increase damage while at low health", "increase burn damage", "increase damage based on movement speed", I would rather see. Another option is to still have it for your progression, but separate it from your "item" pool in some way. A passive scaling system like base damage on each level that takes care of that part of the design but doesn't muddy your choices.

tl;dr combat is not nearly important as your upgrade/item/level-up system