Shenmue 3: 10 Things It Must Do To Appeal To The Modern Gamer
3. Proper Subquests
The original Shenmue had an awful lot of things you could do outside of the main quest - including being able to feed a cat so you could get a few extra cutscenes - but it was fairly low on the subquest front. Shenmue 2 improved things a little bit - as there were a number of secret battles that you could access - but even then the subquests weren't exactly made obvious to the player.
Shenmue 3 should take the tropes established by the likes of Skyrim and other open world games and make sure that the player has plenty to distract themselves with outside of buying capsule toys and playing arcade games.
A decent set of subquests that offer the player the chance to get into scraps outside of the main plot would help to alleviate the boredom that many modern players would feel as a result of the rather sedate pace of the games, particularly in the early going, in addition to adding some meat to Shenmue 3's bones.