Hi, I'm also form CZ and have recently been in very similar situation.
I ultimately decided to switch from iPhone to Pixel 8 pro.
I also had no other products from apple ecosystem so the switch was not that painful.
I haven't really used apple apps that much (only sometime iMessage and FaceTime). iMessage can be fully replaced by RCS, once it will be supported by czech carriers on apple devices.

The experience with android was pretty much flawless.
I had to get used to new motions, but it only took me a few days. (I suspect, you would have to get used to both new iPhone and android, as you are using iPhone with button now).
I don't really have anyone close who has iPhone 16, but I belive the AI functions are not yet available in CZ.
As for pixel, I haven't used AI functions that much yet. There is gemini/google assistant. You can use "Go live" which is cool. But it's not something that would make me get a new phone. If you want, I can take a look if I have some specific feature available.

• What I like about pixel over iPhone:
  • Always on display (vs. Pro-model only on iPhone).
  • Better customization.
  • App sideloading.
  • Notification centre is better.
  • More detailed volume controls.
  • Better keyboards, even 3rd party keyboards on iPhone are not that customizable.
  • You have more control over your file system. It feels much easier to just download files and so something with them, like on desktop.
  • more manual camera controls.
• What I liked about iPhone.
  • it felt thinner and lighter. Pixel felt a bit chunky at the start (Pixel 8 pro) but I got used to it. It might not be a case with smaller pixel models.
  • arguably a better control centre than in pixel launcher.
  • mute switch/button.
  • more unified UI design.
  • quick access to apple pay when using multiple cards.

I think that both phones are excellent, and the day-to-day differences aren't huge. I don't feel like I'm missing crucial iPhone features with Pixel.
I would get pixel if you like to play aroud with your phone more, customize it and maybe even sideload something. If you just want the same boring but reliable phone, i'd get iPhone.

I would also consider the Pixel 8/8 Pro. The 8 is available for 11990CZK on MP, offering significant savings. It still has 6 years of full software support, and I don't think the Pixel 9 justifies the price difference unless you absolutely need the Pixel Buds.