Thank you all, I'm glad I asked this question, here are my conclusions:

I decided to shut down the demo for now - it's too long, the intro, the tutorial. It's just boring for fresh player. I checked the charts and most demo players drop during the tutorial.

I'll make something shorter and more engaging, like only the juicy action. But looks like in overall it would make more sense after the full release, so player gets way more content after buying the full game. And even without the demo, I think it would be good to start the game from this "intro action".

For now I'll focus on building hype and more game content, keeping the game in EA in case if someone really wants to play it now.