Off the bat, it sounds like all of your uses are centered in the home. And, they seem like things you’d do for longer sessions.
The Arctis 5 is more comfy, so I’d lean towards that right away. It doesn’t isolate as well and it’s not as portable as the M50X, but neither of those should be a huge issue in the home. If you like a really punchy bass sound, and can see yourself taking the headphones on the go a lot, the M50X with its folding option and more robust bass response would be better.
The M50X gets recommended all the time because it has a removable cable, a portable design, and a sound that mimics higher-end audiophile stuff. Its sound profile is great for revealing flaws in audio, but still fun enough to use for home applications. Its tuning is best-suited to female vocals, bass-heavy tracks, and classical music. It sits squarely between the pro and consumer worlds of audio.
The Arctis has additional features you’ll probably want since you said you'll be gaming. Its biggest advantage is that it has a great microphone. It’s also designed to be extremely comfy over long sessions, as mentioned above. Its cable is removable, and although it doesn’t fold down, you could still toss it in a bag. The sound is not as immediately impressive, but it still renders audio with good detail and clarity. I think it’s the better choice for you, and it happens to be cheaper!
In fact, if you don’t need the surround sound USB dongle that comes with the Arctis 5, and don’t care about the headphones lighting up, you could save yourself some money and buy the Arctis 3 instead. The actual headphones and mic are identical, the only additional features you gain are the USB sound card and the RGB lighting. Hope that helps! Thanks for reading.