...the very first cutscene of Shenmue I, redone in UE4 to get every newcomer up to speed on Ryo's motivations and send nostalgic chills down the spines of old fans. Then Ryo would wake up from his flashback/nightmare in the first cave to Shenhua singing.
They'd then head off to her house, briefly talking about why Ryo needs to go to Bailu on the way. Introduce basic gameplay like walking/climbing in this 1st interactive segment. At the house, reveal the Shenmue tree via cutscene. Reveal the importance of the Phoenix mirror again via Shenhua's father's drawing (2nd interactive segment, exploring rooms), and they'd make their way to the cave with some tutorial QTEs on the way (3rd interactive segment).
Then, after the cliffhanger ending, it will fade to black and say, again, "The story goes on...". And then personally I'd love to (as someone pointed out above) have it fade back in to Japan, at Ryo's house when Ryo is a kid or something. Nice, peaceful music plays after the dramatic music in the cave. He gets a life lesson from Iwao that's relevant to what's going on in the cave. You get a brief chance to explore Ryo's house again in UE4. And then it returns to China with Ryo and Shenhua on their way to the village (maybe inside the entrance to the cave so you get that satifaction of walking out of it, with the light being ridiculously bright as you walk toward it).