The measured phase resistance of the coils means nothing. In order to build a high efficiency motor, that motor needs to be substantially reactive rather than resistive, ie to have a high inductance and a low resistance. For a motor controlled by an "Inverter" there is no such thing as "short circuit current" (i'm ignoring active short circuit functionality here) and phase current is controlled dynamically at all times.
A EPAS system in order to provide the maximum fidelity must provide torque assistance to the driver, ideally without imposing any inertial or drag forces on the steering system, ie be completely transparent in its operation. Therefore the motor is designed for low inertia, and high peak current so it can very quickly change its velocity to match that of the steering system. EPAS simply means "Electrical Power Assisted Steering" and there is no relevance to how that assistance is provided, or the architecture of the system. Early, low power, high inertia systems were mounted directly on the steering column, but they were bulky, noisy, and very poor performing often having truely shocking steering "feel". A few "city" cars used them for a while, but the gen2 systems such as the ZF/Hella system you have moved to a rack mounted high performance brushless motor, with only the driver demand torque sensor mounted inline in the column itself.
The rotor of the motor must be low intertia because it inertia is referenced to the rack by the overall gear ratio, which needs to be as practically large as possible to provide the greatest assistance force from the smallest (cheapest) motor!
You won't get any info from Hella regarding the driver IC, as that is a proprietry automotive chipset, so you'd have to sign an NDA with them before they will release it to you.
Realistically, peak motor currents of around 100 amps are used, perhaps as high as 150 amps for a few seconds, but the resistance of a lead acid battery starts to become limiting, ie the supply voltage falls with increasing current, limiting the power you can pull from the battery to a couple of kW at peak.
If you have a look at the phase current measurement system, you may be able to get an idea of the peak phase current used, it may use one of three different phase current measurement techniques:
1) Voltage drop across the power silicon
2) Voltage drop across resistive current shunts
3) A hall effect non contact magnetic based measurement system
There is also a possibility it doesn't actually directly detect phase current, just measures supply current and ratio metrically calculates the phase current from the effective duty cycle ratio