Just because you do not like the features, it does not mean they're universally bad. The Samsung App Store has quite a few Samsung-specific discounts and even apps that aren't on the Play Store (not to mention stuff for Gear devices).
The updates for built-in services requiring an account is indeed shitty, but at the same time, you won't be getting updates for apps if you don't log in with your Google account. It's pretty much the same. I can even see Samsung breaking off from Google and running their own solution for all the services (a la Amazon) on a select few models in the future.
Talking to Bixby... You do literally the same with Google Assistant. Sure, you can type, but it's finicky. By the time you type your request, you can do the same by clicking around. Plus, Bixby is quite useful for certain routines where one would need to do a few taps around, instead of a voice command.
Vibration on the home button can be easily disabled, just like on all the other Android devices: Settings - Sounds and Vibration - Vibration feedback. It won't disable the home button hard press vibration, which is a required feedback, so you know you did a hard press, not a long press.
The Oreo update is not taking much more than other manufacturers. Motorola only now released Oreo, and they're running a fucking-near-AOSP build. Samsung changes tons of stuff in Android, and they're only a few weeks behind.
The loudness of the speakers is okay in most occasions. It's NOT A FUCKING BLUETOOTH SPEAKER. Don't expect 10-15W output on a chirper built into that 8x12x4mm space. It's not meant to be a party speaker. Phone call audio is actually quite loud, unless I'm in a loud environment (say, underground station with the train arriving), I usually have it at around 66% (8 steps out of 12), and it's still freaking loud.
The colours are artificial - you think. Have you tried the other 3 display modes, or the pretty handy manual display tuner? I betcha you did not.
Next time how about actually looking around for options you miss instead of shitting out of your mouth?