Januzaj is very good indeed. Most on here would name him the star talent of the generation coming through.
For me, adjusting for age, Pearson, Daehli and Pereira might each have even a little bit more than him. Obviously the younger you make that claim the less certain you can be. Since several of the group moved on from the U18s to the U21s this year, the other half (including Pereira and Daehli) have slipped off the radar slightly because the general U18s performance level has understandably suffered. It could really only go down, since for the first half of the year they were thrashing teams day in day out.
Players in Pearson's mould are very rare at youth level, with serious grit and long-game intelligence to back up his ability. Pereira is obviously excelling so far above his age level that you can only draw good conclusions. Plus I love a technical creative player who can also throw in a really crisp, meaty tackle. But Daehli is my favourite from the group. He's faded a bit in the last few months, but I'll eat my hat if he doesn't become a very, very special player. He's played very wide for the U18s, and I don't think it suits him at all. He's incredibly quick-thinking and two-footed, giving him an edge best used in CAM, for me.
In terms of defenders, I think you never really know until they make the step up. Their side of the game is so physical, and the physical step up is the big one. But Michael Keane is the stand-out talent. I also really like the look of Matty James (plays LB).
I'm rambling. Feel free to ignore any/all of the above. Oh, and... Oliver Torres.