Big difference with USMC reserves vs ARNG/USAR:

USMCR units are often trained at company level, and organized to fall-in on an active duty battalion.

ARNG units are trained, organized, equipped, etc from the division level on down. Do we return to the 'roundout' concept that everyone criticized after DS/DS? Probably not, but it is a significant reason why the USMC can get guys out the door faster as reservists than the ARNG can - none of those pesky BN/BDE-level tasks to train.

Oh, and that complete and total lack of state-level MSCA missions...