I think Adams and Yueill will rotate at the #6 in the short term depending on opposition. Adams against superior teams, Yueill when we want to dominate possession. Whoever is healthy and in form between Duane Holmes, Sebastian Lletget, and Paxton Pomykal can push for time at CM alongside McKennie and Adams. I just don't see it with Roldan and I think MB4 is finished.
As to the CBs I think Aaron Long's days are numbered. He's a solid defender and athlete, but provides very little on the ball. Look for one of Miles Robinson, Chris Richards or (Wake alumni) Mark McKenzie to contend for starting minutes soon. McKenzie has been excellent since the return and is drawing interest from Anderlecht, Celtic and a few German clubs. Miazga, CCV and Erik Palmer-Brown also contending for call ups but i think they've missed their window to breakout. Tim Ream gets kept around for depth and eventually pushed out next summer. Robinson, Dest and Cannon will complete for the two FB spots.
Today I still think Altidore gets the call over Sargent, but Josh is receiving really good reports in pre-season and looks to be a starter for Bremen this season. I can see him taking Jozy's spot soon. Zardes provides cover. Pulisic is penciled in at LW, and Morris, Reyna and Weah are battle for the other spot. Konrad de la Fuente recently became the first American to make Barca's first team match day roster. Doubtful he breaks through this season, but he'll most likely get loaned out to La Liga or Second Divison Spanish side. Brendan Aaronson will get a look too, possibly at CM if he gets a little stronger and nastier. Arriola maybe stays around for depth and grit when he returns from injury.
Also keep an eye on Greensboro's own Gianluca Busio, who is 18 and is starting regularly for Sporting KC. He was recently moved from an attacking mid/forward role where he struggled, to the #6 and his first couple games have been a revelation. Still a year or two away from really pushing for USMNT minutes but he has an Italian passport and Serie A teams were already interested before the position change. He's spraying balls all the over the place, is winning duels and tackles consistently, and scored this beauty the other night.
Honestly I've never been this pumped about the future of our NT. We have players who will be getting regular minutes at Chelsea, Juve, Leipzig, Dortmund and Ajax this season. Lille and Bremen too. Add in our keeper being the #2 at Man City, Konrad on the fringes at Barca, and Chris Richards at Bayern contending for minutes and its very exciting. Dare I say Golden Generation?