Hi @Arwin, welcome to the forum 
This thread is hopefully a good starting point for understanding system power capacities and requirements. The OTPS alone is not suitable for providing 100% throttle of 6 T200 thrusters simultaneously, so would also not be suitable for 100% throttle of 8 T500 thrusters, but it could be used to operate them at reduced throttle (which also provides higher efficiency, albeit with not as much thrust).
That said, if you need access to higher throttle values then you’ll either need a more powerful source (and potentially a custom, lower resistance tether), or one or more batteries on board the vehicle.