Northeast and Godleman were supposed to be the big names from the current youngsters and both, now with plenty of games under their belts, average under 30 and have been overtaken by Hales and Taylor. Stokes and Root have also popped out of almost nowhere and Wells and Bairstow are also making a strong showing. I'm sure that there are others too and of those I've mentioned, Taylor has one of the poorer records this season (in Div 2 to boot). If we were to go down the 'pick a youngster' route, imo Hales for top order and Bairstow for 4-6 look like the stand out candidates at the moment.
There will always be calls for the youngters and most of the time if they are selected they show that they aren't ready, as per the list in one of my previous posts. Many never make the jump to international class, some sit on the fringe and some do go on. The thing is that between 20 and 24 is where we generally find out where a promising young player's ceiling is and/or how they deal with an almost inevitable slump in form. Maybe in a couple of years time Northeast will find his game and be setting the world alight and Hales or Taylor might have done a Schofield and lost it completely, so now is not the time to lob a random youngster into the test arena.
Best to see where they are in a couple of years when we will most likely be starting to look for a replacement for Strauss. By then we will have a much better idea of who is the real deal. The good thing is that we have a lot of names in the hat for when we do need them and if some do drop out, others who may be late developers will surely replace them in any list of 'possibles'.
For now we should be looking at players like Hildreth, who have performed well for a few years, have the right amount of experience, are around the age of coming into their prime and are still young enough to have a 7 or 8 year test career if they show they can make the jump.
edit - One final thought. Four or five years ago, the mantra of the 'select youth' group was 'Bopara! Bopara! Bopara!' and he hasn't turned out to be the Bradman/Tendulkar lovechild that we were led to believe.