I was pretty sure I covered all the questions, whether directly or indirectly, so I guess I'll start from the top and answer them one by one.
- No experience with the Razer Kraken V2. Only worked with the original Kraken, which was not very good, but that was like 3-4 years ago. It didn't sound good, fell apart pretty quickly, and the ear cup material was uncomfortable to wear.
- All headsets except the ones with a USB Type-C connector will work in just about any computer from the last 10 years. Except Apple laptops, because Apple. The thing is USB Type-A. Why wouldn't it work?
- You may or may not need an amp. Usually, USB-powered audio has already been pre-amped by the USB port. Otherwise, that's easily US$100+ in additional purchases. Again, no experience with the newer Razer Kraken. The old one had no such volume issues. I also haven't found any amps with a USB audio output, since amplifiers, by nature, output in analog signals, not digital. Since you're using a laptop, I'm even less sure.
- It's not going to sound worse than a $30 headset, but is the sound quality worth $200? No. Do the looks and lights of the headset make it worth an extra $170 to you? That's not for me to judge.
- I cannot tell you it's going to be better, I cannot tell you it's going to be worse. The human brain's perception of audio is so subjective, that headphones that sound great to me sound like absolute garbage to someone else, even if it's my mom or dad. Your best bet is to choose a song, preferably something with an acoustic instrument, a wide frequency range, and a wide soundstage (recordings of Beethoven's 5th symphony, Bach's organ suites, that recording of some hymn from the beginning of Bioshock Infinite, etc.), wear all the headphones and headsets in question, and try them, listening to the same song.
My personal audio set up is:
- Audio Technica ATH-M30 (Discontinued): US$65
- Zalman ZM-1 microphone: $7
- SYBA USB audio adapter: $5
Still less than $100, sounds better than $200 headsets for both the microphone and the headphone. You might be able to score the ATH-M30X for cheap. Although not as good as the original M30, it's still better than a lot of headphones that cost twice as much. In the states, the M30x is still about US$65, $56 on sale. No idea about pricing and inflation in Lebanon.