As I'm rebalancing the XC unit stats I usually keep certain standardized parameters to ensure intuitive gameplay.
The spartan royal guard however has been an exception and XGM signature unit.
Following the rebalance we can have 2 options:
1) historically plausible stats:
attack: 15
armour:10
defence: 12
shield: 5
morale: 27
1 hitpoint
2) XGM-level stats (proportioned to XC new stats system):
attack: 18
armour: 10
defence: 15
shield: 5
morale: 30
2 hitpoints
For comparison, the sacred band rebalanced stats are:
attack: 12
armour: 10
defence: 12
shield: 5
morale: 21
1 hitpoint
In the campaign the historical unit would get realistic recruitment (lvl5 barracks, 2 turns) while the super-unit would stay with XGM recruitment at 30 turns.
The choice is yours.