Interesting time of arrival. You've just missed Olim's antics.
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Oblivion is another, perfect example of level scaling done utterly wrong.
I don't mind level restrictions on items, but it has to be done right. Runescape is a grind, yet when you finally reach level 50, that Dragon Scimitar feels powerful. Better yet, you're impressed when you see other people with high level gear. However, in Runescape, you drop items on death (much like earlier MMOs), so unlike other games, you don't necessarily get to keep this permanently.
That said, I do mostly agree. Often it is done wrong. A good game will rely on true conflict (like a boss or hard-to-get-to place) to slow down the player from getting those items, rather than on artificial stats. Even Morrowind at least played with the idea that to even pick up Daedric, you needed a huge amount of carry weight... which you could only get with high strength -- a hidden level restriction in a way, and that works well.
III. Loot to kill to loot to kill progressionExample(s): Diablo, Torchlight, etc.This progression of kill to loot so you can kill to loot to kill..., though initially rewarding, becomes monotonous rapidly. Like you're standing on the production line, repeating the same action over and over and over and over again to no real outcome (although, at least in production line work you can earn money to buy a fancy couch you never really needed). It's just dull and uninspiring.
Monster Hunter takes this path, yet its made more interesting by the fact you hunt for materials rather than specific equipment, and then use those materials to craft items of your choice. It at least feels diverse, or as if you have some level of player agency.
Another alternative is to work toward something that's actually interesting, or to instead have a game focus on the goal. If the goal is to slay some super-villain, then let the player choose how they want to go about doing that: will they grind for materials, explore for legendary equipment, or attempt to fight the boss head on, that should be up to them.
IV. Dull random lootExample(s): Skyrim, Diablo, Torchlight, Borderlands, Tales of Maj'EyalNothing annoyed more more in Skyrim than the fact that, no matter which blacksmith you talked to, the all sold the same items, excluding a couple of randomly enchanted loot. It makes the world feel utterly dead, and those items don't feel special. This is something Oblivion did do well, to a degree. Every shop in the imperial district, even if it sold the same items as another shop, at least had one unique item. It's simple, but it at least felt like the items were apart of a universe.
Diablo also has this issue. Outside of a few special effects, most items only differ by a couple of stat points. Its that age old 'If everything is unique, nothing is unique'. Borderlands at least tried to make this somewhat interesting by adding branded weapons. But even then, loot gets dull quickly.
Roguelikes tend to do this well, though mostly because you're expected to die rather quickly. They can get away with spawning in a Cursed Mithril Greatsword and have it feel special, as the chances of that happening again are slim. And even if you reach the late game where those items are abundant, it still feels special as you've had to work your arse off to get there in the first place.
V. Minigames vs abstractionsExample(s): -(using fishing as an example, here)
This is something I see in games all the time. Sometimes when I go fishing in game (as an example, this relates to any interactions), I don't care about playing a crappy little minigame to 'feel' as if I'm fishing. I want to cast the rod, wait a second, and then hear a sound: success/fail. My goal is not
always to have a full-on, fleshed out fishing experience. If I want that, either I'd play a 'fishing game', or I'd go out and do it in real-life.
I'm certainly not saying minigames are all bad. However, sometimes its easy to get caught up in the idea that every interaction needs a special activity. The imagination is powerful, and games can take advantage of that.
Additionally, games can also take advantage of abstraction to create somewhat unique items. Say you're doing a quest line for a civil war, and the general wishes to reward the player. It's much better to reward the player with 'Legate's Imperial Armor', which is just standard Imperial Armor with better stats, than it is to give them random loot: 'Iron Armour of Alchemy', which is completely irrelevant to the quest line. Perhaps if you were an Imperial healer, that might make sense, but otherwise, it just feels lame.
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As an added. I think most of these designs are more about how you choose to design, rather than the idea itself. If done well, all of these sins could work well.