if by "3 angles", you mean "9 angles": 0 degrees, 45 degrees, 90 degrees, 135 degrees, 180 degrees, 225 degrees, 270 degrees, 315 degrees, and forward thrust. I don't know what kind of calibration issues you experienced after a fight, but the worst I ever had was that I just had to press a button to re-center the pointer.
You also conveniently left out all the games that made use of the gameboy connectivity and gamepad that I mentioned would have been impossible otherwise.
I left out everything except the SS bit. Yes, the angles go in either direction, but this can (and already has, for decades) be assigned to a directional modifier. So if you press the hypothetical diagonal swing button, you either press left or right to determine the direction. Which, by the way, I doubt even matters in SS; I think everything in the game registers either swing entrypoint direction, so it sees 45° the exact same as 225° (talking about the real collisions here, not the fraudulent link animations). If, in some RARE cases, this matters and I forgot about it, you could use the directional input to combo the swing direction as mentioned anyway.
And yes, I had to use the re-calibration button+pointing the wiimote in the correct "reset" direction, except I had to use it every time I used items after any sword swing. Which was damn frequently, so it ended up doing more harm than good. If I were given the option to manually aim, I'd have taken it. The non-sword related everything in SS was forced down your throat as far as motion controls went. The game reportedly had wild calibration issues for different users; having the nifty auto-calibration feature is not good enough when you have to do that thing every 10 seconds anyway.
As for the other games you mentioned:
- four sword didn't ALLOW you to go into different zones thanks to the gba connectivity. The developers arbitrarily imposed the limitation that the main screen would not be dynamically split. They made it a "mandatory feature" by their own choice.
- I played Chaos Theory on PC, so I don't know exactly how the cam implementation worked, all I'm reading is reports that the port of the game is overall worse (for reasons other than the gba connectivity), and the information on the GBA is frustrating to read, making it pointless. I don't believe I missed the best version of the game, but I never tried it myself.
- The pac-man example is valid, even though I don't know about the game itself, your description looks like it actually has a reason to use the feature. How many games have competitive asimmetry like that on the GC, though? Just that one? That being said, this is still different than the WiiU case; my main complaint on the WiiU front is that the gamepad was included as the default controller, not that these features exist. The GBA connectivity is an external purchase, like it should be. You rarely would use it, and so it makes sense to not include it into the GC package. Imagine if the GameCube included a GBA+cable because a few games used the feature in a smart way (adding to the price accordingly). And imagine if that bundle was the only option to buy the gamecube. Would you say it'd have been more or less beneficial to nintendo? I say the latter.
- I've played Okami on the PS2 only. Every single person I heard from who played both versions, said that the Wii controls is just another configuration for the game, it doesn't add neither detract anything. They are just there because the Wii did not have a proper controller (by default), so the port HAD to be different.
As for the WiiU gamepad:
It has the second display, which has been deemed "generally" detrimental by the general public, because watching two screens at once that are far apart is frustrating to people (as opposed to the jointed DS/3DS screens), or, like in recent examples, it takes you away from the more beautiful 1080p display on the TV (kirby).
It has touch controls, which I only view as a flavor gimmick that gets implemented just because they are there; I am convinced every game that gets designed today can do away with the touch controls and do something else for the same effect. The only exceptions would be games that completely revolve around them, like say, trauma center. Where are those games? All I've played on the system is optional menu-clicking or minor assist mechanics (rayman) that aren't core to the experience in the first place. I haven't played one WiiU game whose touch controls were actually required. Kirby is universally considered a game that would have been better off on the 3DS, otherwise that would have counted.
It has Amiibo-related tech inside. Well, that one is probably the most useless feature of them all so far; it will never do anything of value to the games themselves, except being figurine-buying bait. Anything that comes from a figurine, could come from the base game itself in the first place, it's just an excuse to make people buy the figurines. Don't care, this is objectively a gimmick.
Anything the WiiU gamepad can do that I am missing? Other than the low-quality yellowish screen, the fact that you cannot recharge it by plugging it on the console for some ungodly reason, and the 3 hours battery life (the deadly combo, these last two), all it does is sucking additional power from the main system (which itself is slightly underpowered), and this is why I think will never be properly exploited with most titles. Also, again, it pumped up the price of the system for optional/secondary features.
Nothing requires 1080p 60 FPS, either, but that doesn't mean it can't enhance the experience.
Anything can enhance the experience, but whereas 3D is entirely optional and does not directly affect how games are designed, system specs do, and it's always a direct improvement having every game running at 60fps against 30. Any game, even a turn based RPG. Any game directly benefits from better stability. You don't "optionally" turn off a higher fps count or higher internal resolution, it's something you'd always want if you had access to it. People do turn off 3D, therefore, it's less useful and effecient to improve the quality of games. The problem is that everything costs money to implement, and so it's just more efficient to have better specs over a visual filter. That doesn't mean the 3D is USELESS, just that it's nowhere as useful as what the 3DS could have had instead.
Also, the 3DS specs (mostly the resolution) forced a lot of its titles to adopt "chibi" visuals. This is evident with the port/remake of atelier, for example. (It's not a matter of them being better or worse aesthetics, it's about being pressured to use a specific style because the system is too underpowered to render anything else as effectively, which ultimately brings less to the table in terms of variety)
I believe it's actually true; anything out up until now could be changed to fit another existing control scheme and maintain the core experience intact. The fact that developers worked on limited control schemes doesn't retroactively make a game "require" the related feature in terms of enhancing gameplay - it just means the devs had no other choice but only include that one control scheme. The first time this would not be the case is proably VR, we'll see how that one develops.