Saint Commander Casella Ingvar was one of the most powerful assets on the battlefield.
Even though her power and abilities were constrained by the limitations of an expert mech that she had already outgrown, she was still able to Commandeer a huge amount of mechs just fine!
What mattered the most was not the relatively small amount of true resonance that she was able to channel through her Knights.
The biggest reason why her Commandeered mechs performed so much better than usual was because she was able to control their operations directly if she chose!
In many cases, Casella felt that it was necessary to take control away from the mech pilots and reduce them to bystanders.
She did not do this because she was an egotistical control freak, but because her combat skills were simply so much better, especially when it came to controlling ranged mechs.