Upgrade systems: How to make them interesting/fair/not-shit

[NeuralStunner]

Many games feature "unlocked" good weapons when it's too late, and you won't need it anyhow.

Or worse, when these cool items are your reward for 100%-ing the game. By that point, most players are probably sick of replaying the same levels 4 times.

Even NewGame+ is 90% pointless when the only change is "you take half the hits to die, enemies take twice the hits to kill". Bogus.

[Reactor]

Exactly! New Game+ would be excellent, IF you could keep at least some of your rewards from your previous game. OK, I get it, starting the game right away with the badass anti-matter beam would make New Game+ too easy, but at least give me a weapon which could serve its purpose far better in New Game+ rather than the last 2 levels of the game, when I don't even care about looking for secrets or picking up ammo, as I'm fully loaded. What good is a reward which serves no purpose whatsoever?

The operation was successful, the patient died.